.Net Foundation Design Reviews, 18 Oct 2018

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From YouTube: .NET Design Reviews: BufferReader

Description

Today we're finishing the BufferReader proposal today: https://github.com/dotnet/corefx/issues/32588

A

Very concerned.

A

This is recorded to keep your secret anymore.

B

Things was not.

A

Just record all its extremes, you align edit all the worlds. You are as a live and live audience, don't go to line team. So let me just go over last time.

A

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C

A

So, basically, the proposal that that can be summarized as and there's two types being proposed: there's you know, there's a sequence meter of team which wraps a bid, only sequence of tea, and there was a span leader of team, but rep speed only span of team. The reason that span we'd have tea can be faster.

A

That sequence, video of tea, is because it has to do extra work when it runs out of this, then, the more existing of an extra call can cause the compiler to start stacks pill locals, which in turn has requests some micro benchmark by D percent.

A

The downside of having two times is that the API syrup is by 4kids I, some api's would text sequence, Wiener, assemble, take span reader and also over parsing a be able to decide supporting both would call to vacation, as you can't funnel them easily through the same Co path, because there's no abstraction because they're, both by definition, something we want to keep on the stack as a struct. And we could do these things. We can ship a third time. They can Rev either a sequence or a span.

A

We can ship to x, one can wrap either a sequence or a span and one that only reps when we can only ship a single type that reps either a sequence pan or ship and non speed spend only one later. If you discover we need the performs.

A

Yes, none of this will work when you use it from language. They don't support rest racks, which I think we are aware and do not care right now.

A

So there was some effect on the API, which I think we can skip, because it's just a typical movie stuff.

D

So, just some very context again is the design by this has driven by two things. One is you know, making it easier to handle the being bifurcated buffers with the sequence, which is difficult to write code to that correctly, let alone in a performant way.

D

The other thing is to actually make it hyper performant for hopefully get to the level like web type performance and that actually drives a lot of compromises in the Navy I search in you know, months and months of like doing repeated measurements with this against probably JSON readers and also micro benchmarks.

D

Even you know the scope of one single if check really like cause a significant progression. So it's important to keep that in mind. You know even adding another argument. You know we have to really haggle back and forth because that can cause. You know magenta spill things over and or not the things and registers whatever and they're like the commenter's up and not like 1% 2%, like things like in higher level things it shows up as like 5% regression, user or whatever. So there's a lot of I added a second example here.

D

If you want scroll down, bikini is over well there's one example: now from David's blog page, here's the new example, so this is actually based on it's a little logic.

D

That's going on inside of test roll right, where we have to three things up: I, carry sure mine to you, but then we're also trying to make sure that the action cab carriage turned life, and not any so in in doing some pros, I'm painting this makes and the rest of the law did further downstream, including it's a lot simpler, because we can do that sort of double check here, I think in a reasonable optimize play. So because you know these things have been hyper optimized. The primary Danny uses the vectorization.

D

Where can you know helpers? It ends up being reasonable performance, so.

E

This thing finds the the data that contains it lying but doesn't contain the actual crlf. Yes, right anyway,.

D

But then you know we're validating that there below and then the rest of the code didn't want to see ROI. They just wanted to know yeah.

F

D

Nothing in there right that it had a ballad zero at the end and it doesn't have another one inside. It's.

G

Not a that's, you know that point.

D

Great, so we're just trying to read to any. This is using one of those. Oh my god do. We have either of those share of determine line, feeds right. You found one okay. Is it actually crlf? That's next yeah. If it is, we have the piece of them. They thought to my things that we're talking about you like meeting a second tall, actually measures. So that's why we have a lot of this advanced passed. A single call.

H

In this situation, caring what happens if you're, if the sequence ends and you're in the middle of a something or other like, is there state to be passed back or it doesn't matter.

D

This one joins it together, so this will this will concatenate into a span for you by a newing up a numerator, so there I have some proposals for dealing with that. You have one of the Lucchese yeah I have.

H

That conversation.

I

D

We go through more the sorry.

H

I would shrink this. The sample function like this would appear to assume that all the headers are in the same, in a single sequence. No.

D

D

The reader isn't returned was that the the.

I

Reader isn't returned so like.

H

You someone calls read header lines. They would presumably need to call it again with another sequence, but there's no state that's passed that it as I'm sure I understand how that works. Oh yeah.

D

This this doesn't need it, because this is a single call in the case. In the case of casual, this is a pony or callback with fans of each header line. This tool is consumed, but it still happens. Well, if that's like yeah, like it returns out, consumed I can't I simplified the example and.

H

D

Rid of that okay, so yes, it will say how far exactly read it.

E

So try we try every to any takes. The first book for argument is the output and then the second argument is the delimiter x'. Yes, okay and I passed. The limiter means it skips, yellow I'll return the line and then is next check. The current. My purpose isn't to see if it the next character its index and characters match. If it's fine and that's I, think that's clear.

J

Then is it matching like one of the elements of this panel is.

D

Nexus met is that's a sequence wrong, so it's making sure that those then.

J

Sequences, the.

D

Next circuit, the the other one privy to any, that's the any part of it. So only.

I

D

Them are there crl.

I

D

Yep, it just so happens that, like you, can use the same span in this case, then this is a pretty common sort of thing. People want to do. Is sleep break things up by C, RL laughter? You can just do that straight out. The menu there's also the ability to like check to see like you actually have any.

D

So there's try read to that I've two ticks of sequence, two as well. You don't care about like dangling.

G

D

Anyway, there are some questions like there's an assumption here that, like in the normal case, people don't really care so much about allocations of that cross segment, boundaries and sequences, since it should, in theory, be more relative. Americans know you have ways to address that, and I want to discuss that. How can we or the EBI surface again just so that we don't get wrappers into that without contact? So if how that fits into our service.

B

A

That's true, though, like isn't, then the argument that the amount of product we have to track. It would only be something that would be ideally very rare like so, if you've ever read, only seekers versus a you'd only spend, but we assert that the Barkers you get past and are usually large enough. That running out of this fan, I'm running out of the sequence in order to go to the next one is rare, then why would that make you different?

A

The huge difference in which market so and you have a reader that just deals with spangles year through reader that deals with read-only sequence right the moment when you cross the boundary from one to the other like the spam, my basic return and say I need I need another span. I've been out of this one and we'd only sequence cases. We just call the method that basically gives you the next the next element in it, but that is rare enough. So it should then also be the performance implication of this case be rare enough. It's.

D

Well, the performance of it is certainly designed around like hyper optimizing, everything being in the current span, so the the issue about overloading the other thing is, if there's also an API surface problem, but like there are things here that return read-only seek ones for good reason, those things that have no meaning of a spandex reader and if it's like addition to which position stuff is also awkward, you can lie and like to weird things, but wait that makes me sort of feel dirty.

D

D

So, in any case like and then getting back to the original point like that, one extra check makes a difference and a significant difference, and that was part of the one that called out before, so that one extra check that ends up being a know off in the case of things that are a single segment.

D

Kills you when you're talking about working with spam, but.

A

That's the thing I've done credit and, like this extras check, you're talking about like I, mean whether you have a span or every sequence. You still have to check whether you run out of space well,.

D

Sure, yes yeah so like you're, taking it you're taking it hit for the, but if you write one, that's specifically for spam, it's way faster to take out these extra chats I mean like doing binary, reading and stuff like that employee. These things are they're all very fat, potentially fast, very fast operations. So.

A

Many might not eat more than long, but like the way I think about this is that when you're on the reader, it has a field summer. That is my current span right, and so, when you initialize it from a span and sense that if you visualize the film sequence, it expects the first batter puts it there right. So all the operations normally just deal with that span.

A

Now, when you actually hit the case where oh our money out of space on that span, that's when the extra work would kick in for a sequence versus pancakes yeah, so.

B

A

B

That would be a rare case, though the sequence one won't be any slower.

D

To have support for spam, it's the span thing that's much slower than it could be so like if you write a reader specifically for Spanish and I did this and we ran the test and that's part of the the other pieces that came into this. It is in some paces, like 60% slower just that extra check. That's a no op right to remove it completely. You get a 60 percent improvement in performance.

A

But maybe I can understand I'm getting it right, but what is the extra check? Your isn't the check effectively like if position is less than spanned on the last part, so.

K

The extra check is.

D

At the end is like you did, couldn't fund it and don't get the next band, which is a no op. If you.

K

Have no more spans left and we always say solely.

A

K

A

K

A

That the check exists in the method- water- that was the holster stability local thing again, yeah yeah I see so the co gen is just unfortunate in that case, yeah.

L

The other thing with come on time is consumer of this time. It doesn't know when they can use position for, like anything sequence related, because if they do what happens when you pass in spend, does it throw alright.

I

D

Will that would kill performance so we'd have to look. Let it just kind of borrow so.

L

Like from the outside, when you see this offender takes a common reader or come on reader of spam or and if the parser doesn't happen to use signal simulator test, you can pass both spam or sequencing, but in case parts of decides to use sequence. Another test you can only pass sequences, will just force friends, they don't have alternatives and we don't have overloads like. If you want to slice a redundant sequence out, you can always tell again I keep coming back to if we even.

H

I know people are gonna not like this, but I keep coming back to whether even want a buffer reader for a read-only sequence and.

G

H

G

H

Know we can get the one that's just for span really fast. We know there's a higher level bit of code around using the buffer reader, regardless of whether it takes a sequence or a span for working with pythons right. There's a there's, a higher level thing about getting the next sequence from the pipeline and then passing that into the reader, and so there's already boilerplate at that level.

H

Is it if you move the sequence related boilerplate out of buffer reader into that level? You kind of coalesce it with the other boilerplate. That's already there. You keep the buffer reader really really really fast, as optimized as they can, and the overheads associated with both going back to the pipeline to get more and kind of updating. Your sequence seems like the overheads they're kind of merged together.

H

So and you end up with something: that's not that much more code and that's faster, and this seems to also kind of gel with what Austin was seeing with Jason reader. The.

E

Different overheads: there is out of the entire sequence, so get more from the fight and there's I'm out of the current spine until next time, I'm bullish, both may be kind of rare, but I think we need to write the perfect code that does the end-to-end see how bad it is I'm, finally, having a spy reader. Only if we also write the boilerplate code that everyone would have to write to get new data I.

H

Agree with you, if, if I'm wrong, if it's like horn-like totally makes sense right but in my mind and maybe I overcompensated in my mind's, the boilerplates, not that much boy little, you already have to write it's it's.

D

Pretty fabulous well, it's it's actually pretty bad yeah.

H

D

Know it's if all you think about is like you're, only gonna cross the boundary once it's maybe not.

M

E

D

Right but there's no guarantee that that's the case and, like you can cross three you can cross for what happens. If you have like hundreds of megabytes, we.

N

Have data for more than four gigabytes.

C

Like a meld on that has- and they want a something that can work with- you know over in 32 max value, Lane yeah. So this this thing is I'm.

H

Not anding why the size of the span matters read-only,.

C

Sequence can be longer than in 32 sure can be alone right.

O

H

Someone's chunking their their input up into two gigabyte Jesus, like the overhead of calling into the buffer reader to process two gigabytes compared to process 40 device like it doesn't matter it.

D

Does matter if you were like actually going to then pipe this thing down through to like another read-only sequence, so or.

C

If that's entirely.

C

It's faster to have one process read in the two gigabytes and buffer it into memory, because you have that space then operate it. While you have a another thread: go in process into the secondary buffer, okay,.

H

I think we're nobody's I, don't understand at all how that impacts this so someone someone should write this deep before we decide to ship either a reader that operates on read-only sequence or either exclusively or in conjunction with span I. Think it's really important to see what these cases look like in both ways so that we can make a choice. That's all I'm, saying yeah.

A

Like I want I think we need to incorporate the feedback from crystal there and maybe because I feel like I'm, more or less in that boat as well. Where I understand it, you want to optimize this thing for performance. At the same time, though, the cost of having two times floating around and that everybody make a choice might make it verse, because you know how to effectively do some crazy gymnastics to adapt one to the other in order to use the API. The only thing that.

H

Lattice point the API that it networks with both also has its downfalls just from a usability perspective. The.

E

Only thing I'm hearing is that you want two types, because it can't be one because writing the code, like writing the code to copy the buffer copy, the e bring the remaining buffer from the previous buffer into a new one, to append to the sequence it's kind of the entire point of this typewriter, the type of tip it's just like doing that, I, don't.

D

Like that's exactly what I'm trying to get at is like this like there is. There is a scenario where it like you just want it to be simple. You want spans out and you don't like any want to be able to just deal with spans, but there.

G

D

Complicated scenarios where you're going to like then take them I want another sequence: it may actually be crossing three other sequences and then I want to pass that thing on again.

G

D

Then split that thing up again and like you can't do that unless you actually continue to use the sequence mama so I mean my argument.

A

Would be like I mean it was just one option to have one type doing both, but the other option maybe have is we only have one time and then depicted sequence for that, and so everybody really wants. The last pair determines usually like the code. I mean like you want to be expands your style. You want to get the last month of performance out of it. Well, that's what we have low level.

B

Processing you guys.

D

There's a plan, and that's and that's that was my kind of culinary argument: I, don't really see people actually using expand reader right because, like the look in most cases, the data that you're starting with is going to either be something like sequence or it's going to be an array do something you can wrap it memory that you can then wrap in a sequence right if you want to be using this thing for those things that that's like stream. Reading of some sort, we're not gonna be starting with a span like people know how to.

L

Enumerate through an array that has an indexer throughout them character,.

F

L

A sequence winner is that you that there is no throughout indexing like if she freed only sequence had indexer. That was free. We might not need this type of, but the problem is that you cross segments and you need to keep track of your position.

D

L

Where you are and this and that so.

D

So, like I, like my real proposal here, is not really the creative staying reader, it's just that. That is the option if we find that people actually want it. My my gut feel is that people will not want that because it's like, if you're at the point of having a span already, we already have all it's really nothing more than a triage thing. You have slices for you. Yes,.

E

So that's like the main thing is that it it was place for. You I, think that place I've seen it. People want to use, try, read big endian into whatever, and they have to do slice for slice for not to call him that, and it means you have to pass this time there. If, if you're, passing to helpers, because Bank isn't given to do that's kind of what more wanders so I.

H

I'm happy to be convinced, I would just love to see the following I'd love to see like take. This read header lines. Example I'd love to see what this looks like with using it like only using the span constructor as part of a larger loop that operates on a pipeline.

E

You just copy the code from Castro they catch them. Does it today, yeah.

H

I think we're trying to come here it we're trying to look at usability in purse, so for each of these things, I'd like to understand what the user build like what the code looks like and with the purpose for side by side. If you're you just have your outer you here, you're you're, using pipelines with a buffer reader optimized for span, doesn't work with sequence compared to you're, using pipelines with the buffer reader. That supports support sequence.

H

L

H

We look at those two things like your I believe. What I'm hearing is that the first one I described is going to be more unusable than the perf wins. It provides, if that's true, then okay, ship, the single buff reader, that suppose support, sequence and span, and you know, and we'll deal with the rest to fall out. If that's not, if I'm, my theory is right that it, you know it yields better perf and not as bad as we think usability. Then. Maybe that's something we should really consider, but I could be totally wrong.

H

It may be horrible usability and not that much better perfect, and we know that suited me.

D

So I I did there's a copy of the customer code. That's in for thanks, lab and I have a change that actually converted it over from using bite stalker to spam, and this chunk of code here now I gave up something for like moving from bike spotters fan because there's nobody to make that II equivalent. You can get close, but you can't get a couple input.

D

It's just the nature of the me, but I made it as fast by taking advantage of this and like I know, you really know what capsular looks like, and you know what this fits in here, but like these things that made its way way simpler. If you like, you can there's a lot of logic in here. That's trying to like do the stuff between the way this multiple segment.

D

It wasn't this thing yeah and like no we're gonna pass part of the carriage return light beats I, won't stop it like the rest of the cells trying to look at it. That's where I got the stuff back from yes, I.

E

I know because we spent we spent the entire. The entire tooth will release half of it, trying to write a fast parser like a book like that type different net on their own I.

E

Me ended it with what we have today and it's super fast I mean the best way to do is to drain the span and then, when you cross segments to use the reader right and the whole, the hope is that the reader can you, trade have some performs because it won't be as part of that, but at least it'll be fast enough and readable. So you can are in the middle, oh yeah. It's.

D

Much more readable now I mean like again if these are so effective pointers and followed. This yeah.

E

D

Would still be faster, yeah.

E

G

D

Can you can yeah you you, you can do really well with this and I'll share. What that looks like I'll actually make the PR actually haven't. I have the PR for that good I'll share, though the PR is for it. Yeah.

G

D

Was just some argument about whether or not I should so.

P

One thing that was I was explaining was building a reader like OTS on October span based reader. Why can't we do the same reports here? We have the buffer here, that's based on spam and paint a sequence reader on top of the spam build because it's slower, the sequence. Readers know.

D

You're adding another layer on top I mean you saw this in your own measurements, all.

Q

Matters in my measurement does.

P

Secretly tactical clattering mmm the sequence for your base like this or here he goes, video sequence, pastries, no-hitter, but faster. If I'm leveraging the span based.

Q

The calls have you made to the buffer leader.

D

Right, every call that you may make another call just to advance like didn't curtain your performance in the significant money, no performance and.

H

Are you saying that it actually yeah.

P

H

P

I'm not use if we separate just reading, but for you an exercise was every bit somebody expand based and then build a new, only sequence based on dog. That's what I'm, Tiger yeah I got.

D

That, let's just say, like you're calling of the existing buffer reader every like you made one extra call: it tanked your performance numbers. That's why we have these advanced to you in advance, past operate and specifically from consideration your stuff. Now the same thing would happen if you're wrapped around other things, that, like we're going to adding another level of indirection, we have to make another call where the jet camp, like collapse, things in the same way and like you're, you're, just gonna take another five ten percent of the worst performance head.

D

So because, if the measurements, we were really trying to imagine what was really optimizing for the single segment case and then also measuring for the prospect major into that. Okay, but like I, have you know micro benchmarks for each of those things? Maybe.

P

I was thinking like you. Those calls will not exist anymore because all your quizzes are on span based, so the extra calls they advanced to over over again will drop down to only when you actually need to cause bound use. If you are wrapping sequence-based reader on top of the spine base reader, the presumption.

Q

Is that, like you, don't want something that then passes out.

D

Sequences and I don't think that that's what we want, so that's one of my fundamental arguments is look. We want something that still passes. You need to be able to still. You need to be able to still parse into another read-only sequence, yeah.

G

It's like I want.

D

To try Ritu and due to the scenario that I have I, know that I still don't need to I, don't need to span if I the whole thing. Yeah I'm gonna be grabbing out at a smaller chunk, which is gonna, be less likely to be crossing boundaries because none of this or where I just need to know some extra data and some other parser. That's gonna get this read-only sequence. That's gonna then wrap it to a buffer, get around it or do whatever it needs to do like. Once. You start basing everything on his fans.

D

You know you're you're done. You can't do that. So yeah.

L

D

Somebody writes out of almost read-only.

L

Sequence: three: there: it is to get to the size of this plan where it's very likely is not crossing or anything yeah.

E

You pay for a copy at that point, so you see you have a giant line and you split into some segments and then you find the thing that is small in the fact that you don't my allocating trying to expand and you park that thing into it and then you move on and the other part, the other big part is keeping track of.

E

The position is important, knowing where you left off, so you don't have to rescan the buffer after you finish, is it worth for the pipe star, so you parse a buffer and then you're like halfway down and you you you from the parser the pipe meenu's to advance from there and it doesn't have to ReWalk the buffer from where it started from so keeping track of where you were when you ended. Parsing is what it's nice little thing and we're hyper optimized for giving you.

F

Bad position matter.

D

That there's a proposal in here which to add an unsafe position to make it even faster because, like in the reader, we know we're in a segment yeah and we're like it's just offset this thing. So I added that down here you'll see the.

J

D

J

To be, is it the position that you're in spun or, and this spun, oh? Is it like they're, so.

D

Like the the sequence, position is an object and in it and there's in the case of the the read-only sequence, there is a flag that sat on it's kind of an eternal detail, but, like it ends up, it's like significantly faster.

D

While we've done a good job of optimizing, trying to get good position and what I see all? Is it in this segment or not like all those extra checks in going through a couple, different methods signifies a significant performance hit to keep in traffic position here, because.

J

We've already done all that, but yeah okay, I'm, not not solution to the memory. Questions mostly like is the position like a global position.

E

E

Excitement index.

J

Beginning from from the epic.

D

D

Anyway, can we go down and look at those sequence api's to give some context.

E

Of this I'll say one more thing about the crossing boundaries, even though it's rare the way pipelines works is that bump the buffer is kept around. So so forgot your bucket, and you don't want to pass in one a woman wall, my buffer, so imagine you had a fork a buffer and you used up all the one bite you wouldn't use the last bites and pass the read.

E

You allocate a new buffer move on, or so we end up crossing boundaries and more than you think, because we don't want to drain eat our buffer for 4-perf reason. That's right! You! Never! You never want to pass less than some minimum of data to the actual thing. So if you didn't use it the entire book from the last read, you may end up passing. You know a bunch of the difference in the last segment and a new segment to to a parsing API. So.

P

Why would thank you, David.

H

I understand that makes sense to me at the same time. Doesn't that also, in effect, sort of often mean you're going to have at least some minimum of that of data that you are passing to so the buffer readers is some number of thousands of bytes or whatever, so that there to be a lot of processing that happens before you get to a sequence, boundary.

E

It depends because is it first request that that diamond end up being covered? If a request is big and you don't end up parsing the entire thing, you may end up passing the end of the people opera because you may not have had the entire thing in a single segment, so you may, you may end up. You may end up allocating more more data in a second in a second segment, even though you still have a valid request in the previous segment. Let me find so.

P

E

P

E

P

And the first request and those partially cool requests and that there's one less buffer than the end of it right and then you.

E

Know anyway, right on, we wanted okay, and you want just because we still will use the old buffer if it has room. If I had enough room see me end up crossing, even even though you, even though you could do better. If you made a new array that I have your team in the first place. So.

H

E

I understand that I understand that.

H

There would be ways to optimize for the number of buffers, but I'm saying it seems like with this approach: you're also optimizing to it to minimize you're, still sort of guaranteeing by some definition of guarantee some minimum amount of data that will be in each span. Yes,.

P

Yeah yeah yeah: how do they get the frequency of stragglers.

L

You request start from from.

E

Zero from the.

L

E

In in theory, right if we were to return and the array everything we consuming the entire class, you start fresh with a new, a new array. Every time I see. So you start from zero and go up up and tonight there, but we just start where we left off from the previous class, seeing me and using the using an old block, even though you, even though you would have had a single block if you had made- and you were in first place.

H

Let's say your threshold was even like you know: how's the size of the buffer. If half the buffer isn't remaining.

E

H

That's still 2k worth of data you're passing in a span jerk.

E

Cookies are 4k, that's one header sure are jumpy enormous.

H

Amount of work processing- you know two thousand bytes and then making another call in processing. 2,000 bytes, maybe I'm wrong about the cost here, but that the processing of the two thousand bytes would seem to dwarf the size that the the extra call in that case back to processed and expand. Yes,.

P

Okay, in my case, I'm about to like less than five ten percent, okay.

E

Put this way if I run plain text and I and I didn't have the code to optimize for parsing expand out of time and I just wrote. The quota assume that you could display every time is everything.

H

I'm not sure are.

E

You saying that the the perfect you take on the buffer switches is minimal, because it is rarer than the actual part of the buffer before it went.

H

That was my question. Is that true idea, I'm, not sure if you're saying yes or no.

E

It's tiny, if you, if you do parts of spine up until switch yes, but that's that's true, that's what this is not most were think great. Yes, does that and.

D

Takes away its, it is very, very difficult like again, we can write something on top of it as well, but like getting back to the other point, is that, like this is also optimized to span to do as little span a fine as possible right to narrow it down to the specific scenario to do it until you want it? You know so like if you're, if you're saying that, like we have to complete copy, you know, copying becomes like almost mandatory, then your. How do you how you find the next presenter.

H

Crossing we've already spent 40 minutes on you know appeasing me, so we can move on. I will I'm, not sure that my request has been heard. I will write that I always did correctly. So let me write down what I would love to see and we can go from there and one here. So that's unreasonable sure, yeah.

D

So we'll talk about this alligator alligator.

D

Let's talk about the other I.

E

Mean I get it, but this.

D

This is for them. You can you're crossing boundaries yeah, if you don't want it to just interest into it, and I'll explain how that works, but I want to actually with all these things that I think it really helps to see what the surface area is like what these api's are. Then you can get some more context, so we changed some names and we got the end like this is one that was a little tricky.

D

You know I'm not really sure the best way to do this, but you can do some pretty good optimizations on the user name and if you know, there's no more getting it coming right. So you are in the last segment that you can sometimes utilize that that.

E

Helps really, including and decoding the included games the cumbria again. Yes, so you say it last segment, so you.

D

Can like you can do some hyper optimizations on the other side of it's like well, I, don't even need to bother because I know I'm in the last segment. I have this much data left I know you can too I know I need to go back to the pipe and ask for more right now, before going and trying to make game worried it. So.

P

One question I had was around the concept of a spinal block, so we don't. The frequency that never accepts concept is final ground. So let's say you have really sequence that ends in a number 1 2 3. But the pipe has more data as possible. The numbers 1 2 3 4, yes, but you would return 1, 2, 3 and say that I want that yeah.

L

But the reader is limited to what I can think to read on my sequence that get passed in, so it doesn't matter how much right like it depends on the logic.

P

That's it but it's possible for the pipe like for you to go back to Piper, get a new sequence that has the natural extreme end of the digits, correct.

L

But this reader only appraisal read only sequence that costume right, so it doesn't matter. What's inside the.

P

L

Right so my question is what.

P

Happens if you have a real sequence of 1, 2 3 and the pipe has data that clip is about 64. You say Rinat give me the next day as.

D

P

D

Like it won't work, it doesn't work for more look the binary. Well, the person doesn't work like that. Okay, so we can change that, but we why don't we get down those evil eyes? First and Jan talk about, particularly because there's a lot of caveats that give them that you do not know where the end is right.

D

The so like the other option for this one is supposed to sing like at last segment. The only reason I thought about like doing it as a specific helper, because really what you're looking for is that signaling get objects? No all right! No.

L

It's not the right logic to use because there might be another. The next segment yeah, so you can be done with sequence, represent sure.

L

Give me empty okay, right, you're, checking next segment. So no.

P

But that video, particularly only sequels next segment, would be no right. No, it can be a third segment give a writer.

R

P

Is only sequence? Alright, the view is because you've got its next segment should remain now. I know, you know what doesn't have a.

L

Sequence is two positions and in position.

L

Position is where you stop us, no matter what's after it, and you should never look, you should never even look past. You.

D

Think the answer here is that, like we do, need to make a helper method for that, so that, like people know that there's another like the thing I was looking at. Was that what you don't have you have the ability to know the calling? Next right? It's not going to get you anything yeah, but that's implemented as.

L

Current segment, yeah.

D

That's what the Friday, so we can iterate on yeah, but so like just doing it yeah.

M

Well, how would it work.

P

We have the advance.

D

Of rewind, we talked about that last night, very importantly, useful when a good cyber optimize, of course prefer not to think about that stands for the front of a house, but the case. The normal case is that you're actually just want to know I mean if you.

D

J

State and consumed of course it's just how hard so on, if you already or anything, by few bytes on me and that's the expectation every. Why not take int or short or something if the the basic scenario is to rewind only by few bytes, you push the realignment on, but.

S

You can still go back to the previous.

J

Part because, like it's too case doing like that, he taught me Sigma, so you can.

D

Distribute out to the preview Jean you can back to Brisbane and again it's it's a it's a performance. What you think it has to be is.

J

Fastest, what, if your sequence, three there is like kind of continuously reading the data, and you can never come back. Is this the kind of well when you have a read-only.

D

Sequence, you can always go back, it's when you go back and go back to the pipe again and ask for a very lonely sequence. I say then you're any different. So.

J

Dislike the current one is their autonomy and figure so.

D

The other way to see track of things is to actually keep a copy, the redundant you and I together. It's totally random answers in in the specimen in the renal sequence that you have until you're. You said that you move forward given live, then you have to get don't so.

D

The current span and the currents being index and the other defendants just basically helper for that puts the two together. If there's a cost to that, of course, business license the.

G

First time and.

D

In the sequence position position was the actual position sequence position thing in the head, something that efficiently and then the original sequence.

D

So we go down to the actual things that you know the person here and we change the names and these based on feedback from last week.

D

So there's try reading Trekkies.

D

So they're trying track being pretty straightforward. That's what's next give me what's next move forward and what is peak so he furnace fan I'm thinking of fun, so this one's the more complicated one, because, like again, it's optimized for being super fast and there's no need to copy in those cases. So.

G

D

Slices and gives you back so like this, that that thing they've got copy buffer is like if you have to copy copy into this right. So we use it all the time internally, looking you're doing binary parsing or to find the actually. But we look to see if we have enough space in the kerf in because we do that for super high problem. The slow path is like: okay, we'll stack Alec and that's.

G

D

Other method, and then peek into that is it's only if we do the same for parsing, because we wanted it into 222 bytes, so that.

H

Copy only happens when you cross between seconds correct. Yes,.

E

I love what it does that, if you guys super hard to understand it is, it is very hard. I was getting so like I'm, like that one I'm willing to linger or.

D

E

Ending so brainstorming would indicate that that that the copy, the thing you packed in.

E

D

Do you only call.

E

D

Comments for this are very verbose. The other thing to do is like pétain.

L

You literally think I'm look you find the buffer in and then you never use it again.

L

O

Basically, passing in scratch space that.

H

You can't touch again.

E

Because maybe I can call it that scratch over or something's, so you know get you see me I'm within the stack allocation right, yeah.

K

E

The biggest downside yep see you could never get a funk.

G

E

It won't work, you can make it a span action, but then your taking it to bosnia, delegate to yep yeah.

L

Just use it for small buffers yeah.

D

That's that is very, very it's very it's what it's intended for! That is what a to towards like this, these small scenarios where you run over and you just want to grab it nice, which.

H

I mean what is this: if the copy buffer is insufficiently large, it's.

D

This also tells you that a TM is what a passive like if you basically they're copy buffer, is also telling you how much data you want and if it can't fill it, it slices it. So we use this logic internally as well. So, like again, your person.

G

H

So if I want a peek, let's say it's got a and it's got a hundred cheese in this pan and I want to peek into that. To get a hundred.

G

I actually have to pass.

H

In a span of a hundred T's in order to get back or we'd only span, the existing buffer. That Rd has the space.

D

For this one and it's a convenience thing, and then you could build all this stuff yourself. It's just like this whole thing of moving forward without allocating or is actually or changing the position to keep track of the existing position. There's quite a bit of logic in there to do that. Yeah.

E

Do I think I think it is like doing a funk. Okay,.

D

We have, we have other matching things in here like this. That's.

L

That's the other end. How would you need you need aspects place in the code method before you even call this.

E

D

It is truly the most awkward what API we have in this, but it is against a Tony is useful. It isn't super.

F

D

It's just it's very hard to express precisely I mean without putting one you know, 30 character, long. What's.

E

The number for the the the biggest size of this despise you should pop in there before it gets too expensive. Well, you shouldn't be doing anything more than 128.

J

Respond for the input: this is the return which is kind of just.

D

Got this is the this: is the it went through design review this week for language design. It's one of the pending things. One of the problems we have right now is that what you cannot express? Suitability and the current checks can't know that so like. If you stack Alec, you can't use the nice convenient. You know unsafe yeah,.

G

D

You can now with this, you use the read only, but you can't change state, there's also another one. So this is like. We can't modify this, which we don't need to in this case.

D

So that's why I've added it here, just kind of really call that out and I have a section down below explaining that have been also explaining, where we're still missing it, so the other places that actually take a span where we actually have to move the state you're still stuck in that case and we're there's there's a proposal that bumbling around in the background to like, have a no captured keywords or something those longings that allows you to say just so like.

D

If you pass in a span, you can attribute that the terminology can change, but like the no capture would basically prevent you from capturing and it allow it to say, like oh sure, go ahead and test the span and even though you're passing through this thing, it's a wrap. It's not gonna hold onto the stand, so I don't have to warn you about it or do anything get out the slip into a trust. I know.

H

You put it on the API. Is that don't mutate and that take a span, but presumably you would also put it on methods like tripe, a crane.

D

H

Still immutable and you still would want to call that from an API design perspective you'd still want to call out its it's not mutating this to the callers, since we have that ability right sure.

D

Sure I just put it where it was actually a problem. I guess like. If we can add it there, we should it's it's fresh off the presses, but it like I was addressing a specific problem. That's listed in the problem section, it's really hard to use this because you have to use it to deal with bugs a morning, but you have to do this time so the unsafe to do it and it would be nice to get out of that because those things are in progress, it's partially there or there's another solution to fixing positive.

D

So we changed the terminology on some advanced stuff. So we looked at these next.

D

S

E

Identified that one better I.

F

A

Peter from last time was because the names were all over the place was to actually use advanced everywhere. We do isn't.

H

Any singular, well, isn't the word any a singular shouldn't be is any next.

Q

C

Yeah I think it's already are any of these choices applicable versus.

T

Maybe just any mixed just a full. We.

E

Can too many out.

T

E

It's a very Java style. You get any of like.

A

E

Next seems, fine, isn't it well? This is kind of this is a boolean as well I mean I, don't mind, pudding is a.

E

Kid you and they.

G

Don't know it isn't it thank.

E

You, like you, don't.

D

N

Okay, be the any neck says when you're running.

D

Rubbing rubbing up against the other honestly.

G

There's a difference.

J

D

Is next can look if you pass in multiple things? Isn't access like that's a secret, maybe.

J

One hand versus an.

D

Orrery, what.

E

J

E

So any is yes, any is from linker is any, are what any really do either work.

S

One off sounds like one of learning so.

S

H

Have for like index I'm here in.

E

No actually sounds good, though some.

S

What's index often I.

A

E

S

E

Just ace of any is any is.

S

Any in any that knife.

E

H

I

Given the next thing is important: yeah.

E

I

You I'm gonna.

H

Like that rolls off my tongue and it matches index.

L

S

H

Also, a subset of his next is the next one. Any of these I.

A

Think NASA Navy big was also like is next was weird people suggested starts with which.

K

Gives it will be starts.

A

K

A

H

Dream is start spent on a reader is I, don't know whether that's referring to the present position or the initial position. I.

D

Said what just next? This is quite no.

J

S

D

Binary reader text reader, but like it, isn't those different yeah they're just consuming.

E

L

E

There's nothing like checking for the check in the current spot for the upper yeah. It's new, but.

D

Super important when we're talking about like yeah keeping position and stuff so and as we iterate as we constantly use these rate I. Imagine Rothman. Has it well.

F

Even in area, even in my example, we showed it you're like they don't expose it to you. I have a demo. Similarly, accelerator.

P

Has is start a limit.

E

So I became record. I am NOT similar.

A

At Becky, it's called something like looking at.

D

In the present yeah I'm happy with this is next and just like a guy that groups them together, yeah.

T

Yeah, we can continue.

D

To iterate on these advanced.

T

Okay, let's focus I like personality first, so actually.

P

T

With imagination.

J

P

Leader and it start it has the same problem. It is not going from start of the underlying purpose from where you are today. Yeah I agree.

D

With it, but for me, I have that that's I have to go look at the documentation I have to because, like already starts, we see ones there and what was what starts with right, because I would have to move to know this. It's kind of he's any next like well. This definitely involves position.

D

A

Coded peek token lawyers are passing an offset yep I.

H

Have a question about these optional advanced pasts, so you talked earlier about individual branches being able to totally screw you, and yet, where did these api's sort of necessarily have an extra branch that has to check whether you're advancing past or not, whereas, if you had two overloads where one could assume the value wouldn't have to do that check? Did you experiment to see whether that makes any difference it.

D

Would make a difference? I was just trying to not give a hundred api's in the first review so like how do people feel about going to that level?.

B

My personal opinion is I.

D

Guess I can make it in action. Is next.

B

In advance generally, don't care about overloads because they don't increase.

A

The concept look at that much again they're more in metadata, but it seems funny like I, think Judy. We prefer defaults now because it makes it clear what the default is, but it evolved intelligence, but I mean quite frankly whether you have try be two of to overloads or one I mean dad well.

D

What was the one thing that could express? It is if it was his Nexus and but it was and then of the other ones. Where is next and advance right I then there's no question about one last question and all of the behaviors well.

A

Would you ever positive false explicitly? Would you ever want a positive false exclusively? If you would I can take basically is, is advance ever going to be something that would not be virtual.

J

What about like are any nice, how.

A

J

If the bull should be one of the values for immediate.

E

Actual I guess for those ones, maybe those should have to be returned. The thing that you found for the innings. How do you know which one you you saw you say all right, I mean x, one two: three, that's a good point.

E

How do you return true on.

D

This one it's hard yeah you'd, have to have a holiday. We had this somewhere else. You'd have to get up to do it now.

D

Yeah well default. Go team, okay,.

H

Presumably, if you care about that result, you're gonna be doing some sort of switch right. You hear me saying if it was zero, if it was one if it was two if it was three if he returned negative one like we doing other things like index up, then that would just be another case in your switch statement. Oh.

D

Do it, it is to me mm-hm.

C

Heroic return, 0 return, 3 exactly.

H

I didn't match anything in return.

J

L

Always in are you returning position.

H

L

H

Think that was a different question. That's question is I call are any next true/false. Am I calling the.

O

Overload yeah am I calling.

H

The sorry true true true, if I passed true true true, am I calling the first alrighty next overload or the second already next.

B

D

H

There was a very clear answer.

D

H

The compiler will do and probably no one's gonna do it. So maybe doesn't matter.

A

So I mean my question: is initial, most more like if you, if you, if you pass in the advanced processor Ventura as a variable that is depending on stage rather than it neutral to literal Falls, and if you make it an overload with a different name. Then well, you do Europe by date. But if you, if you expect this to be either true or false, explicitly on the cold side,.

B

Then, having two methods is one, that's that's! That's. When I.

D

Expect but wait it's not like. We have a lot of use cases yeah.

F

D

Got it coming some days what.

E

You've got a use case coming I got some people that have used BBC is in their playback copies on three years of different franchisor readers, so they should be getting feedback on using this. In so I'm gonna I'm gonna go with.

D

The like blowing these out, we all, would exactly we look into the air and look again to get at the perb. Yes, we'll have more surface area. My boy over there all the same, we're more consolidating the names anyways or making comparable, because it does make a difference that x-ray check to know whether we enhance or not yeah and.

E

Let's say going through, the pipeline's review will be in experiencing was making eight days nicer killed. The perfect lot of cases then.

G

E

Took it took this little long time to get it back out there, for you guys so yeah.

D

So advance past and advance to I think we can do this see. The other think this is another awkward because, like these will definitely return where they advanced to yep, but you don't have a. We want to return, the concept of which one we get oh, but this is a good.

H

D

H

So I understand that chairman key shaken so.

D

The advance past return long because they returned how many day advance. But.

H

Those are the bends in a sequencer, but.

O

I guess it doesn't really matter. That's all 317 spaces.

H

In a row, I would returned 17 when, if I passed in his face right well,.

D

You would have to track all of them anyway, because it's an or situation in this case right so like which ones in in advance pass well I, don't know that, there's a way to actually represent the same thing in before me. One of this one is, it could be all of them. They could be one of them. It could be. Two of them does.

H

That matter, though, like is there a use case where you want to advance past several different things, and then you want to know how many of the shoot advance past that's.

D

What I'm saying is like no so I are.

Q

Sort of going down that wall, whatever.

P

So is next anything return. The value you want he found and I love is sort of the connotation.

D

We hit something, you know we have a branch there or accept the value and we need to keep the one we're coming to measure. That, of course, did does what we've been doing already you'd like to see. Can we keep the end of every turn? Eight at the end probably do.

F

The digit surprises.

D

D

If I, if I, see that it's actually slower for some reason, and what weird is it, the presumption here is that it would be faster than check return, that data.

D

D

These the try we choose, the one that returns is fan in one of the sets, and this is the allocation.

D

So that's where my other things come in, so like one, the initial thing that I started with is like really. The answer is like: if you care about the allocation of the span that you were asking for like in the cases where you were going across segments, that's you have read only sequence to take care of that. For you, you can do the minute. You can do this stuff there.

D

The only problem with this like so you can take the sequence out and I've made that faster or at least put this other proposal for the look. You did because sort of fast index or fast positioning, but it is still slower right, so to call that one. Yes, it's optimized to look in the current span to do it, but like there's a lot more stuff in that map, the whole thing it's just.

D

It is a little slow right, so the fastest one to go through is the thing that returns to Spain, because what you just don't have to build those sequence. We don't have to do. There's a costume in the sequence right so I'll see, man can just end up being a slide so.

E

D

You think that ends up being pretty fast and it's really hard to beat that so.

E

One issue is that a bar doesn't work for these because you returned to the first the the first argument so to do. Try Ritu out bar. It would just feel right. Yeah.

P

D

So the other thing that I was looking at here was having allowing you to pass in and delegate basically that plate says for any number of reasons. You can do this like blonde. You could say like ball and one of the examples I was going through the Stephan last night he's like saying, but you have a you: have a loop for your name, you're doing a whole bunch of stuff, and you know it's going to.

D

You have a bunch of segments because that's the way you use your stuff for the way it's set up whatever and or you know, you're to be calling in this a new look. You have it out and now the reader, you have your own buffer in there that you keep for that. Out of the thing yeah.

C

D

Because you know you're always doing a sequential, just always use this one, and if it's more than this I know was going too far for you think about something that we thought is you know this is already a problem for people that are current api's. Don't give you the ability to cap it size your lights. So that's one way you can do you think on something you don't winery, then you tell well here's my allocator for that. Yeah.

G

D

The biggest thing I will ever- let you do is this so like how Richard I'll just throw in the case where the buffer reader comes back. It says: okay, no I need I, need a gigabyte work for them for Strings pennies for this right. So that's one way of doing that is to wait. You use that way. You could write your own wrapper.

D

Then, like runs from the pool, attracts thing things like renting and returns us and disposable, a raping tractor, etcetera, etcetera, I, don't expect to come easy use, yeah I know we'll be meeting it very often, but I think that it's a useful out in the alligator.

E

Thing was down, there is a, is a type or delegate it's a delegate at MSU, so.

D

I can iterate it just that's why I started like having it be and, after our type would work better than fine and okay, whatever whatever's most performant, so just something that takes an engine returns. His fan, yeah.

A

We don't have that, unfortunately, in Spanish.

D

You wouldn't want to stack out like for the this is this is typically the big scenario is very like or potentially big. This isn't like sixty four five. If.

E

You when you implement the five new readers, not trying to parse the little endian 832, you don't call this. You call Pete first.

D

The the actual exact algorithm is supremely. Why do I have enough in my class, fair, yeah I? Don't then I call this other method. Just gonna make the JIT happy. The other method doesn't peeping into the stack outlet.

A

B

You just have a constructor that takes is expensive used as well, because we can't store.

N

Span in okay, this is a rough one. This.

B

Is four times it has to be because the.

P

28 because I mean all operations are like small right. No, it's possible is like his point is. If you have get into spanning two segments, it doesn't have to be a string, it doesn t work 28 and we allocate and say okay, your strings right here and it here it is for bigger ones.

D

P

For bigger ones, for.

D

Peak I start with the bigger ones. Well, we would, if you passed in, like it's possible, we can add that as well for some of the other scenarios, for you would never he'd only stack.

E

Out with the ones yeah you could make, you could make the Peaks fine, you want pasta in upfront and then you use that for all Peaks. That's one option. I guess.

E

D

Think it's definitely worth exploring where.

E

Else, do we need I'm, not.

D

Sure how useful I think I'm definitely worth looking at to see like if there's any one design like if that's something you need later on, without breaking anything or whatever yeah? How? What do you like allocated like? What would you risk.

F

You doing that locator! You would probably go to the buffer pooling because I can't return it before then like. How do you return like.

D

I see before you try to use it well because, like you're, you're being called you're, something called right watch.

L

Along because there is no point in limiting it to spend- and maybe you'll want to allocate it on the sequence and if you can leverage it to do it.

L

There is no advantage to having it being spent. You sure you cannot do stack a lockers that goes away. There's one advantage. Man guaranteed.

O

That you're guaranteed that.

I

O

The sequence we delegation can't.

D

Store it yeah, you're, right, yeah, but and getting the span of the memory is actually slightly slower right, but I don't think we, but.

L

This is only way you'll do something like new binary.

J

Because you could reallocate the stock and then use inside of the delegate, you could you just give a sponsor.

D

You see saying like you, could stack, allocate the way in and help you, but you you're the love to capture when.

L

U

L

A

But you could probably do it with stack a lock and unsaved.

D

Of course, the uh given the other ones, the other way to do this, of course, is just get in those cases just use the book that we read only sequence but you're gonna pay the price and, in the cases where you don't where it doesn't again, creating creating a read-only sequence is not free compared to like slicing this fan, you sliced a sequence or a huh you. You sliced, if a sequence been created. Fifty two three yeah.

E

It's based off the.

D

Position, composition, composition, annoying thing, so it gets yeah. There's.

I

D

I

Only you have to construct that.

D

Object but you have to learn.

D

Three free shipping cheap, it is cheap, but it's.

G

D

Like we're talking about the fork a buffer or scenario like his chunky, yeah you're,.

G

Almost never calling into.

D

That and then or meaning that extra functionality leather. What the rare case where you do that's internally, the way we have this implemented right now is in, like the span, all the things that do this and stuff they try to work on the stand. Then they call a helper that does the the read-only sequence and then they like use the read-only sequence to whatever I do.

E

Generalized and level of things to cause looking that returns you, if it's, if it's, if you meet if it needs more space.

F

E

That pattern we called trade blood hasn't this moment, that's a smaller, so.

G

E

Could you use this to replace that pattern, I guess on top that kind of uses this to allocate name so like what one of the options.

D

That we were looking at for the actually based off the field life last week was actually redoing. This thing is, though, it always returns to positions of some sort or a length. The problem is: is that like currently well it's it's, it's really hard to use. Yeah and.

G

Then you can direct with.

D

Like some finish, that I'll get to your second click, the problem with like doing this things, and then you have to return some sort of quad with quad. You know state because it's like well did I. Did this the operation do what I expected it to and okay did it have enough space?

D

Did it not have enough space and, like you look, it goes on like you to like, do a lot of sort of juggling or turn into like three different outs to like, like here's the result and then here's this thing about the bomb that.

G

And you'll and that's in the.

D

Buffer and like it gets pretty awkward, so it can be done, but it's super awkward and it kills the pervert, because then you have to call back again and to get the data right. So that's it's back to again to the point that I keep beating with a stick. Is that like every single little thing is? Is.

E

Not freak, so do you think if this makes the perfect better, because you don't have to cause I, wonder you to have this pattern more places that have the whole tray tray black pattern that returns false. If you can and.

D

Some of the clear like, as far as like expanding that out part of the reason this makes such a big difference is because the work is going on here. Yeah.

P

It's just simple yeah.

D

P

Not really what David your session, the author he's saying like maybe based on status, based pattern with this, using this they're different from what we discussed, which was change. This do you know terrorist attacks, yeah.

D

Well, you know I'm going back to the operation status. Thing is like why we didn't go it this way to illustrate like we did actually even look at that or he did I did well making this new operations statements, but he's talking with the other opposite. They are worse. So.

E

14 yeah I think today we added a bunch of a bunch of calls on like various API is to return a status and a bool and other other things, and.

G

E

If this pattern may be easier and maybe more perform in some cases, instead of having the caller after we turn up in respond over and.

D

I think the fundamental thing is: how much work is that thing doing yeah the.

J

Difference is the main strike: do you actually need only one operational buffer where you need to focus for maybe like so I like in terms of this? You could implement that, so you could connect something like pre-allocate one span and then, like kind of delegate, you always give the same kind of buffer and then like whenever you look, you always get the same kind of data and so I feel like the kind of talks will be like the only kind of useful scenario but like you can implement it with in terms of this.

J

So I think like this I.

D

Think where this doesn't work isn't like the part right doing this pattern, look it's like. We constrain parse and that's the next part. You.

D

N

Struck because I need to get pointers, can't.

C

You just use unsafe because there's a number of tight I don't want to use them safe. No, no, like the system run compiler services on safe class, there's a number of types which are not unmanaged and can never be unmanaged, but which are political and may fall into the category of things. You might want to use this for.

P

H

There scenarios for this other than bite me char, I'm, serious.

D

That's that's all I cared about drugs, I, don't know so like I didn't feel it was necessary to artificially restrict it any more than that because, like I really.

C

Short said, look close.

D

An inside look, I can kind of imagine people wanting to do some stuff with bad or like heavy, but like I, really wasn't if somebody finds a scenario to use it with some struck, that's like you couldn't meets the unmanaged thing. Fine, I'm! Ok with that, like I, don't care like whatever, like we're designing for my bites in.

N

Carton I think I'm the holdout at.

C

The top the other problem is that unmanaged may not be supported by other languages and it's only usable on c-sharp, seven, three and five. So.

G

If we just had struct.

C

And had a constructor check for like its discipline type, then that would probably meet the same purpose and be more usable across languages. But is.

N

A global type is.

C

Expensive, it's not expensive for primitive types. It may be more expensive for straw per user structs, but that would be a one-time check in the constructor. We.

D

Grade the subject for.

E

Sure, that's that's.

N

I'm actually measuring the instruction I thought. The purpose of about four bytes and char is fine yeah, because it's for.

C

Like biting char, you can just have a type check which will be optimized the way I want it. It.

H

Give the two issues you mentioned so for 7.3. This is only a shipment on eight core three, oh right, so we don't really care about 7.3 or not, and.

C

O

I, don't really care about them doing it like.

S

Why would you do that yeah? They.

C

Might have other requirements for a proper other purposes like I mean that doesn't work in VB, it doesn't work with f-sharp at the same level, because F sharp has a different unmanaged constraint. Well,.

A

I, don't think he's all alone, some refs.

H

Trucks don't work in VB anyway, yeah.

A

So that's why I would say: I, don't care about that part, but I mean I, think that so that means we should look into this, because we had other HS that we consented to unmanaged and I. Think John gave still nothing on this that you know.

C

A

C

There's a new champion proposal to basically make unmanaged completely pointless because it would allow you to start taking pointers of generics trucks which, if that happens, then you know unmanaged.

I

C

Because you could just take the address of tu, it would be the statically checked to be the.

N

Only reason I'm doing it is that.

D

Look again, I can, and just for that I would jump through hoops. If you can share with me.

H

I, don't think we should be it's fine if we can get rid of the unmanned.

E

H

Hurting anything great but to me I, don't see any use for this other than fighting charm, so trying to expand it to arbitrary T's doesn't seem like a particularly something. We shouldn't spend a lot of time. Yeah.

D

I won't I agree that won't like lose any I won't take a hit to bite it off the charge to make that Capitol. The construction water builds again they're wanting to construct a lot of these there's already a problem because of the size of the thing constructed.

D

P

Why are you suggesting there's excess, not useful by a child, doesn't have anything on their surface from the opinion I.

H

Haven't seen anything.

H

It's just you're trying to add things that would make it more usable with other T's is sort of Edmond finger shouldn't do that unless we have a real use case, but we're trying to pick up line on the having trouble.

P

We go through the closet right, that's the bottom from you and wire for biochar only, but how do we restrict the color so that they only work.

H

P

Not saying we have.

I

To I'm saying we shouldn't go out of our way to make.

B

We got under the first ones, so what did we say about Edie last segment? There was some feedback on their own right, I.

D

Need to iterate with them about the actual implementation yeah like we need a method there. I, don't know that we can iterate on it. When you try having people trying to calculate that out on their own. It's not a good idea. If.

P

This method exists only sequence, if said emetic, this already miss you guys would be even eat it here. Oh, if a method that does you are mental, our segment is just unreal receivers. You won't need hearing it's. It's positioned, very.

Q

Straight so like.

D

Yeah, because we only expect we only keep two positions, you can tell it straight from sequence position than great I.

D

Trust you will agree but, like that was my argument. I thought it was that simple and they're like well. If it's that simple, we should just enclose the sequence, perhaps and put example.

U

Good intentions, yeah.

P

I, just about ask I really do if the delimiter is not found. What is it return in try to do if the delimiter is not found? Does it return the entire sequence or just returns? Nothing! Nothing! Privy!.

D

To it has to be successful, so Bouboulina found something and false means it didn't yeah, but.

J

D

J

Know, well, you know how.

Q

Far, it went because.

D

Q

So if the next one.

D

It was string, split.

Q

P

It didn't find it in your dozen attachment. It's.

D

Not try spit so you know you would be able to do that because if it would in your logic, if they return false, then you just use whatever to take a little process. So.

E

They try this out like yeah.

D

E

V

I read advances.

E

It has a true knowing.

P

About advances the.

Q

Vault is the vault is true.

D

Yes, you're normally, but.

Q

If I sell, our you know, go.

D

Back up again was it true.

D

F

It's true yeah, but.

D

Tomorrow, there are some cases where you don't want to.

Q

The one of the room yeah but like I, thought the normal way.

P

Q

P

Q

Only fun and then that's.

D

All does it that's the delimiter. It's as a manifesto women against bosses update the guys, try read, they doesn't make any sense for again video defeated territory, yeah.

Q

D

Move so so using extensions. The idea like we have this one you can kind of ignore. We don't have a utf-16 person, it's a project yeah, but that conceptually that's the idea. Is it like? We do a utf-16 parser, and then we have one here that a set of extensions that a star but the try parses that take the fight assume everything is utf-8.

D

E

See charms which are different well I, kept seeing the same ends of the with the white versus charged in the main difference.

E

D

We have 16.

J

Come soon like new and young man became young, they were so like, and but this same API could apply them physically should be some kind of way of telling encoding.

D

Sure it's sort of all there's more meant to be more innovative, because we have a fundamental problem. We need the utf-16 with you, because the behavior we didn't do it the first time around. Is we have these other parsing stuff? The problem is, is like you now choose over this one. Is that, like the actual semantics of a utf-8 person are radically different and we are going through all like our existing parse functionality within the framework you tell it where the data is utf-8. Parser tries to find that out on its own right.

D

So it reads until the very first not valid piece of data right that so it has it has. It has some fundamental issues and like this is one of the things I had to deal with here. Is it like our current? Our utf-8 parser will take, for example, any number of preceding or trailing in significant digits for most buildings, so you can have a gigabyte worth of zeros and it will happily read off to know early and that doesn't work very well when they talking about crossing segments.

G

D

Iterating on those for a while wait, Kristoff in particular, you know and I spent several hours talking with acid, about new life when you take in like reading floats and all the other things that come out of this like once, you look at all of them. The only real sort of cross or rational thing that we can come up with is like we won that all of our parsing to essentially 128 teams. So if we can't make a positive assertion within 128 Lutheran, we don't throw, we just return false.

D

So that's what you get so like the basic. It's all highly tweaked to be efficient as it can be in the cases where you can, without tying in too closely to the actual logic, is. The hope is that, like you'd, be like I had additional formats in the future. We don't want to have to feel like iterate on this, but the one scenario, if you like say you're trying to read on the hints it has 100 or 200 zeroes in front of it. You know you would read like say it's all.

D

In one span, you have 4k well yeah we're gonna pass that span over to the other one. It's going to read out some ridiculously huge yeah, and it's going to read this back and say it consumed 220 bytes, where it's a you know, that's over a max. So what we're looking for is like it consumes less than 128 and returned successful, but.

E

D

Also have question if.

E

You person in them across the second you parse of pipe that clock segment by DZ anything harder and harder. We.

G

Should, at least as we start out, look for.

E

Those cases would want you take out 128 and you caught me walking up to 128 bytes. Okay, again.

L

Only a minute, whether it one put it the first because zeros.

C

N

You're configurable a minute.

C

N

D

N

D

Is if you need more than that quickly, you can do your own, but like it's, we get.

L

Q

D

Pass one for us to write around some arbitrary number: that's coming right, Jason and Emily to make a decision with things around it like what happens is like we would have make some sort of trading rules. You passing you say. Well, we want to read. 10 is amazing. Well, you can't even get a.

D

F

Like all that complexity, I just said, work very well.

D

128, it's very easy to document that and if that doesn't meet your needs, if you really need to read or you eat it, you have multiple choices. You need to handle this thing where you have a whole bunch of zeros ahead. Well, then, you skip pass penny and then you separate yeah. It's good best.

E

Jason's already advanced best, you look for their first, you find the end token before you parse. They know.

L

You can plug them in and then checking exact.

M

Words, good options, yeah.

C

M

C

Case that I was for you, man, there's, like 128, seems pretty small they're like if you're parsing, the lava Tina, that's not even sufficient to take advantage of like a vectorized algorithm to make this plan.

G

C

Because that's only eight Reed switches for 16 byte and that's about what you normally do: inner loop for a search algorithm, an.

D

N

D

Point here that may not people may not be aware of, but all of our float parsing is hard capped at 50, significant digits that might get anything well.

D

That's part of what drove.

A

The honey in 2008 you see under 28 tonight to take a look. Oh, is it just independent of that? It's.

D

What fit everything in seemed rational would be put on the stack.

J

In the cases where we have to put it on the stack, we don't are they today I'm kind of curious, because, like there's couple of other laws like date/time and like the kind of depend a little bit on globalization and like how like each country like kind of formats, the invariant there they're like.

D

All the stuff that's there is like this isn't completely future proof, but it is attempting to be semi yeah, semi, flexible in.

E

Much as the price to be added in it call it call comp that it calls the UTM a person.

D

There is an option like basically we have. We have multiple options right, we can use the utf-8 parts, or do we like duplicating log? Very bad utf-8 parser does not really handle this idea of, like things didn't work out, the chunks, so in utf-8 pressure is also still based around this idea. That, like the end, is the end so like which we already have Milla straighted. That there's another caveat to this.

D

It's like well what if you go back to the pipe reader for more data and that data was going to be valid like well the current assumption in here, or is that, like the end, is the end so like if you read, because that's the other full thing on it too is like well, if you read it said true, and it was less than where, at the end of the buffer right, there's no more sequence in this latter seconds, then that was the that was the right number.

D

That was the one two three so, but this is the same as what you gave watch. It goes right. I thought. The whole point here would be no no, but the utf-8 purser does not do that. For so we consider the read only sequence, the end, the YouTube, a person considers the spam. You so is.

P

That fight for you guys what do I mean the fact that really sequence that you have in the sequel to its concert at the end, so there Jen yeah. What do you never have an issue where you numbers are trending segments of pipe leading? You.

L

Have to tell the separator, after something of wearable aids, to know that you're done yeah, that's a requirement to part something and then say next thing has to be dois, so I keep our saline and then you purchase a new person in and then you search a.

D

Space or a comma or I think.

L

These are, these are relatively open-ended.

D

The kind of thing is throwing up here, there's like do we just always make it require that you have 128 bytes want.

L

P

Where you can build this new bus and it's one two three and so Jason doesn't necessarily have to have a delimiter. It could be a single value, one two, three: what validation? What if I have a payload.

V

P

Just they did 1 J 2 J 3. So how do I know it's 23 is the arrow is about a 3/4?

P

L

What I have to do.

P

But the buffer does accept.

L

Is it no but into jsonparser yeah, it's information that person has to know buffering. It doesn't.

G

L

So you have like these. Our next thing is M or do something.

R

D

So arguably, like I mean the other one which is releasing quad mole is to recreate a whole nother set of partners and I. Don't really want to do that but like even if we did do that, we would probably not do what you TV. We would actually have some sort of concerns and things like it's. It's unfortunate that that, like you, can be in that state, where you can have again like multiple gigabytes worth of stuff, that it well you're limited by int. So there is a cow okay.

P

D

Q

P

If someone's the oak bags some integers, no no the other way, and we not miss number that you actually read.

L

P

You consider adding.

L

Size as an argument well.

D

Yes, when I was at on calling him, that's it's tough! Well because, like we we're trying to be highly optimized like what happens if you pass like, we have to check the size if you passed in, but you passed in the size that it will never succeed, you write it or look for breaks. The rest of our logic, like we've got some hard-coded stuff in there, or sometimes like for.

N

One concrete example rate still.

C

Have to handle that needs that the remaining bytes in the reader is less than 128 like if you, if you're, if you're, trying to parse and you and we have for my clubs in the span- that's less than 128. So we stopped yeah.

D

But like I like I like to do it is a very specific size, so, as the so is a it's always four or five bodies right right. What you know I deal with that existing someone I would have to win an additional.

C

Because in both cases, you're basically having to say that the limit, either whatever the length of the span, is or it's whatever the upper limit so.

N

D

Is one of the problem? One of the other issues with that too, was that, like the additional arguments would have to be passed through to the helpers and the helpers would have to then have additional logic in them to decide whether to stack Alec or whether to keep bastards over? There would definitely be significantly more complex if.

L

I, don't care about seems so hundred bytes. You don't I'll get that much text place, even if even the so.

D

So you also have the ability, you know the.

D

What your person you should know, because you don't again, is using utf-8 ports. The.

E

Hard part under it.

D

Does but you can do that yourself, that's so you get P! Okay, like you know, like you, really want to be constrained and I want to put that in there. Look if you know that, like the next eight bytes is your int, the one it's going to fail anyway because, like what might be beyond that is more valid in data right, which is not any.

G

One now so there's.

D

A number of reasons like if you know the enemy, you should be passing you. He is highly optimized for that. So.

A

Sorry I'm like how do you like? What does it mean so like I'd, say, I want to parse an end and I know: I have a maximum of six bytes, but I expect I would I use.

P

24 ready use data, look six bytes, Spanish advice, you've got bastard ready. Now you spend and you bastard, you keep a partial. They filled it with six bytes Oh.

D

Or if you want to be extra fast.

M

D

D

Or your TriPeaks are all calf, because you've done a whole bunch of them in a row, and you just make it simpler. That way, because you're using the same scratch buffer all of them and.

P

Then you advance possible in size of the return spend was here yep. That's.

Q

Essentially, what we're doing internally, it's just like we have to deal with, maybe the deal with, but even what do you keep a cluster you're trying Thank You that bastard times bites? Let's deal with.

D

Additional optimizations about it being sort of semi unbounded.

D

These are much easier to implement.

Q

This is the buyer of you.

Q

Should the amoenus be boo.

P

Or machine and eNOS, maybe.

L

P

L

Of protocols are so credit, I would say, I'm just and I am going to India, so using machine dependent engine that that's been my.

D

Experience she was like Google. A machine format. Specifications are almost always like a very specific nd in this. So if you don't care about Indian Hills think.

G

D

Because you have like, like think about reading a header out of something and you have a struct and that wealth attending this is already reflected in your struct definition, or should be for most things, if not you've dealt with that, whatever you do be greater than that structure in the case of the other ones like you're reading, through things individually pieces of data, your respect actually tells you the things that's separate and I didn't bother. You can cast it yourself to the other bits and pieces, I. Think I.

B

D

To upload means in this context, is.

B

For which one well I deal with making a boolean right like it's true, bigger lady right, it's not very clear one. Oh this.

D

Is forever like ambiguous, called sides which ones he's talking about like if we have tried.

R

But we tried read int.

D

And it was passing in big-endian little-endian.

G

R

G

You have to make it clear: you have to use any moment at that point. Why don't just put that you know in the method and then when you're done, okay.

B

D

You're, just using name are you but yeah. So.

F

These are the ones again.

D

There's not a lot of work, that's going on here again. This was the sort of thing where, like it dies, when I'm trying to expand. Look, because if you do a span over this, that's where you.

E

E

D

D

Well, that's there's plenty already.

D

There's plenty of.

F

D

There's a you can do anything you.

D

E

D

A

Teammate, maybe you tiebreak long unmanaged, ripe or recce, as we call.

E

Four strings get anything four strings for creating actual strings, no yeah from bikes; no yep she's. No! That's that's! That's my.

F

Future's I agree, but people yeah.

E

F

They're living dot.

E

It bytes to string pretty much that working across lovers, it's one of those most common ones, I've seen people a sport without.

L

So many met by the right. You think creative use, but no multiple segments well, because you know I see yes, I.

D

Think that one.

A

I definitely want to iterate.

D

On with you guys- and the people like I, just didn't get there yet accustomed.

E

D

Is the baseline so like these other wanted to add an extension to buffers so.

U

D

Is to address that part of what go I want to use the read-only sequence and I want to like put it together myself if I have to well. Alright, we don't have anything for people to do their way. We.

E

Actually have this in the four places and capture any similar and.

D

E

We do we do to.

G

To span to spam.

R

And the fact that it's efficient.

G

That it doesn't allocate, in some cases a better optimization than the fact of it does allocate. Sometimes when it's called a mat, it's like as make me, think it's free another.

H

Benefit to this being an extension method rather than instance, but that's.

D

Just asking you.

L

I

Thing was that.

L

We did that explicitly for.

I

D

L

That was one super high.

E

F

D

Right so I'm, fine with that.

F

I was just from compatibility standpoint. It started with extension, the only thing, though, the boxing.

E

In at buffer here that will problem where you get the alligator yeah. Well, the thing is source have a limp yeah.

G

Well, you have to allocate don't you hat you'll.

E

Have to place that in so the usage is you slice first you've sliced some max length, but.

G

Then you'll have to allocate something to be the copybook that.

E

She doesn't get filled in you. Can this use the the spine was about the alligator pattern. Dude I can't refer.

F

Though that might be a little better, you cuz.

E

F

What yeah I agree front.

E

If you don't have to.

D

Like actually that make some sounds nicely, then we get even set up to know a little alligator on its own yeah Depot, elevated.

E

E

P

The kisses already exist.

Q

Right, oh, this static class, oriented opposite so the last one here.

D

D

S

Know but just put that inside in.

D

The real own sequence as well I, just I, didn't know that we could and we can make it not not.

L

Browsable I don't know, I wouldn't make it.

L

E

To find and scared dangerous, do you know you're doing? No? Yes, we already.

A

Have market types of this yeah.

E

We have that sequence: smart.

A

Oh yeah put it there see this mark so.

E

That okay, dangerous, get unsafe, dangerous same.

A

Is enough, like you know,.

P

Become are gonna have to make it, but if it's equation watch that we don't have keyword there, we just use names. It's not.

L

Unsafe from the way that your process would crash is dangerous, it's just you might get well. You.

D

G

Might not mean anything. Oh.

D

Yeah, when you go and use it.

G

V

Using different conflicts.

E

V

Let's watch it then be sure just use regular name.

G

D

Enough place, I think that's fair! It's like again! That's the this is not like this. Is you won't buffer overrun right you, without with, in the end up of the Navy, you won't get a Navy out of this you'll get an exception somewhere problem you can offset into expect yeah. Well, there's.

G

That that's that.

D

Or you'll end up with a you'll end up with Ranger.

G

K

A

We have, we have put things in the Marshall and the with the unser prefix, even if it's not itself being a Navy, but the scenario is very often you do it and interrupt by the way you really want to avoid the additional costs of calls. So in that sense, I think unsafe is fine. I think we only have one dangerous, apri defero, difficult, dangerous, something you.

P

Have something called unsafe.

P

A

Have dangerous what was dangerous, dangerous, dangerous ranges.

O

And less dangerous changes.

A

Handle and just really it's like there's very few examples like most things aren't safe. That's all prefix, we have kind of said, although for better over.

P

This is going it and sequels washes. We don't have any unsafe.

A

That might be true because we said it's on sequence market. So you know the name implies you.

E

K

Be using against interweb services.

A

We have everything.

K

How many of them say it.

A

Says in throw up services, it's dangerous, so.

D

But he can poke man. You look at the run through this really sorry.

D

P

That it gets distracting beyond sequence position, huh the sequel, the update, see conclusion: oh wait: internal.

D

Detail, that's like the bit flag, things and internal details. Yeah.

E

D

Yeah, don't like it so Gary. So that's the.

D

Futures extreme convenience- maybe something so I agree. We need something and I need help. I can imagine.

D

A

You actually posted API.

W

D

The December I thought it was a simple what well this yeah. Oh, this was just showing an example of other things. It said, like the other thing it shows up in person.

D

All the time is that, like things are set up is like yeah, the adnf stuff is like everyday and it would be nice to write these things for people right because, like you want to really count overloads and say, like okay, well, I want to order these things together, because it's that's what the rules are for this thing, you can be smart about this, probably like quick early the bytes, and only take these senators really clear to define what those rules actually yeah. That's straight.

N

Out of the street out of this bag right.

D

Right so, like I would link here, I didn't put the the RFC number, but it.

N

D

Be everything here would be by RFC Nuria, whatever anyways I've.

P

Done a lot of parties.

I

P

K

To parses your graphics file formats and.

D

K

Are so much okay.

D

This is all around illustrative work. We clearly.

K

D

Already brought the string, stuff and I think that we can live without the easy enough stuff, but that's for anything going have people when trying to learn. Oh you guys, even more scary yeah. So the issue is allocating spread across segments. Yes, we that's a whole like adding that a allocator thing. The.

G

D

Sixteen car, sir, so we can't do YouTube sixteen good unless we actually get that thing up to save in shipping. So what.

B

Will we put these guys that would just the other extension methods over what exactly what do to sixteen percent.

D

B

Would go worry, tube, a personal.

D

A

So you're not talking about any extension methods into the extension you're talking about that I. Definitely don't.

W

Have the cost, but not.

A

W

We do we just didn't, but we didn't finish it right. You haven't.

W

D

The YouTube a parser was iterated on by somebody was no don't have to track all the because it's really good. So I won't.

E

Unless, first, I wants to.

F

D

That I I wanted to string on those before the other thing. The parsing must be bounded. That's the thing we talked about YouTube a parser is not really specific.

K

D

K

Guys doing on you would.

D

So sequence reader can be used inside. Do you see methods yep and there was later than the by design, but there's a mitigation coming where you can make this.

D

So I'm calling in two pieces this can't sound Karen without see if I called up the one.

G

D

The being able the peak thing to be dealt with because we're not modifying the state of external struck so does read only makes this read only the other ones. We just need to say that we're not captured and it's they're not down to one there's, not an issue for that yeah. It was there's a number of other things. I'm talking to Karen about the things coming. Sorry I only said that. Why can you use the same things because.

B

S

D

Current the current the current check that c-sharp does is it says, oh you're, calling a method that takes a Spain one ready in that method is on something: that's a restaurant so that ref object. A recap. I just find that so.

B

W

We need we need some way to.

D

It's another thing: it's just: it's doesn't matter when we get it so rad structs, but.

B

It can never accept the stack allocated stuff then well.

D

They can they use that the world unsafe they.

E

Don't know didn't bother ly hard to know the.

D

The current proposal was that, like we have, we have another another attribute that you had. You know whether we're using written existing neighborhood, but there would be no capture so like you're in you're in parameter would be no capture, say my god, whatever the name is going to be just don't get caught up on something constant yeah.

H

I, don't understand the next one. The sequence reader is large. It says passing my reference is necessary to get the best performance. Isn't it necessary to get functionality, because this is a mutable restaurant, yeah.

D

Yeah? Yes, so if you you're, if you're keeping track of state Oh stream, yes, you have to pacify breath if you're not.

H

O

H

You're copying these things around. You have bugs. Yes,.

D

I'm just calling it out because, like that's that's their bad news, we need another good one with.

E

That came up before how many wait block, possibly.

E

Copy you do want to copy this in some cases, that's so W scenario, but so we do. We do copy it. So, in the current person we can we do copy it, because we don't look the peak sometimes, but so.

O

You can rewatch to.

F

Go forward and yeah.

E

G

E

It got bigger because we added the alligator yes, but it's already ina.

D

Tipping point so it's.

E

Literally, like.

D

Over a 90 bodies because of their weight because we have so many objects in it, the objects have armed force. So it's worse than a.

E

Regular, we did see big curve issues with regard to the constructor step house. Boxing title not even big I, don't think that maybe also a big problem and.

C

In chat, Ben, Adams and chat is asking about if there's going to be memory, barriers and additional costs for having the delegate be a field rather than a parameter.

C

Because you're going to be paying for the allocator field in size and the extra copy cost, and it will cause a memory barrier every time you kind of have to read it. Every.

D

Time you have to read both of you: yep I, didn't measure any curve changes when I changed been using the ball on anything is when you get back so many things would be needed. How many things need this very few that doesn't come up off the ventilator crossing.

A

It would only be a few methods it wouldn't have to take it to anything. Maybe that's workable, then oh.

D

D

D

Did not measured by the way any impact on I have an artificial thing, wrong, parsing or reading outside.

D

N

C

S

But even though the thing that's on the stack and I.

L

S

L

Nothing can change when it's in this stuff, so yeah I.

C

A

Never barriers are really four deep objects in dishes. Well,.

C

The delegate is a heap object, the.

A

S

When you read the field.

C

It has to say locations I, think it's the safer there.

A

But the fuel reading all right allow for the grandkids to be on the stack right.

T

A

It's a restaurant.

D

And some of these look good God says you know so.

L

I thinks guys online converted the person.

L

But you can even replace the reader by sourcing.