OpenZFS OpenZFS Office Hours, 2 Apr 2015

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From YouTube: OpenZFS Office Hours with Justin Gibbs

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OpenZFS Office Hours with Justin Gibbs, April 2, 2015

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Another openzfs office hours.

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Our host today is justin gibbs.

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It's been a long time since the previous office hours. I think.

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About I year or so.

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So,, thanks to linda kateley, for.

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Organizing this and setting it up.

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So let's go ahead and get started justin,. Why don't you introduce yourself and tell.

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Us about you how you came to be involved with openzfs.

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Sure., I'm justin gibbs.

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I work on petabyte scale, object, storage systems for spectra logic.

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And my introduction to openzfs came through freebsd.

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Freebsd has had zfs ports since sometime in 2007.

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And spectra logic, basically.

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Was operating using opensolaris.

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For doing its object, storage based products.

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And at the time.

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That the oracle acquisition occurred.

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Someone at spectra logic decided to switch to freebsd and that's really when.

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I became involved with trying to convert their existing product over from.

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Opensolaris to freebsd, just because there is some concern about what trajectory was going to be with.

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Opensolaris with the change with the oracle.

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Acquisition so the rest of my background.

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Is mostly for freebsd-based., I've been hacking on freebsd since 1993.

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When freebsd really started and.

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Mostly on the storage side, scsi subsystem,, some virtualization,.

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Filesystems., that's mostly what I've done.

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Cool. so I'll start off by opening this up.

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To anyone who has questions for justin., I also have some.

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So questions during that up, though, and if, if you guys, are feeling shy but.

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um You is anyone has a question to start this off.

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I'm go ahead and yourself or I'm on irc, just a.

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Spit out in the opens, the fs channeling all related justin.

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Okay, while we're at it will be worth the your questions.

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You all asked I'll ask you answer on what.

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I, what do you think.

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So letter of these on what's but why did you on.

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Start using open zfs, I in your workplace, like what.

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Were you involved with that decision or word is to make the decision for you and.

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How on why they decide to use odds with us.

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As opposed to some other search technology, yet.

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So the initial decision to use your pass happened before I keep a special, a check.

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And that product was really envisioned as a fusion.

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A virtualization, a virtualized storage.

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And the ability to do a.

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All things is your best already had really.

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Give them a leg up in trying to do that, so being able to snap shots and.

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Creates evolves and things like that, so the original plan.

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Was essentially to provide.

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Just about anything that you could wanna storage, appliance.

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A very ambitious goal: no in fact,.

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Cadbury, when my coworkers talks about is the swiss army knife storage systems.

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Right so you could do nason, you could do so. That's it. You know.

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S&Amp;P and fastened I kinda stuff and have while some just for that, where you could.

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Partition of the walls and launch virtual.

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It senses up such logic works primarily in the a.m. Any business.

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And so a lot of times those offer packages, one runner windows.

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So happy to actually run those in the box so happy to have separate machines.

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So actually started.

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At spectra logic, a lot of the focus was just on virtualization.

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How to get sent to work with previous t&b.

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And have high enough performance when all the storage is backed by cf sd balls.

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Who so a lotta a lot of pain in a lot of.

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Learning about how things like ntfs work.

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Especially when you're going through a tiny straw, no.

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With all the fertilization, penalties are trying to get that those requests all the way back to is your past volume. That's running on freebsd cool scope, a lotta, my initial interest.

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In of his own, optimizing in tunisia past come from.

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That perspective are goals, have changed since then.

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So more, it is on object, storage,.

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Not virtualized storage, you, but a.

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Still summit at initial work with cfs kinda colors.

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My focus on on the bus, cool.

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So so it sounds like it's really the first to tell you that. That's that.

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Initially on was the initial driver there to be able to do whatever you want.

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Well, for that matter, clinton's the other aspect of it from.

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So there are the requirements for sure at the upper satisfied.

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But I think a lot of it was also pushed by being burned in the past by hardware.

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Raid cart room, so there were issues with.

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For more bugs in and adaptec raid card, they were using.

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And, of course, the defender was unable to replicate, the issue should be running.

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Into you, they had no visibility into the firmware, and so the city overtime basically said.

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I want to control everything so if there's a bug.

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I can fix it into the product as it stands right now,.

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Apart from the machine bios and.

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Some pizza for more than the expanders a farce, ass backplanes.

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On we pretty much have access to everything source code for everything.

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Yeah I, like a condom engineering yeah, I'm create a couple. Good questions are.

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On on irc, the other persons kinda related to.

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I your you talk about virtualization, so I'm jus asking.

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If there's any best practices a essentially for running.

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Zfs, on top, is it that so, for example, a.

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Running a virtualized environment, where you have.

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The fs as that running in the on.

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Hypervisor, essentially and then also running zfs inside the guest.

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The arms I'm do you have any tips or her best practices for how to get the best.

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Performance there yeah so as it stands today, the best choices to.

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Create an underlying zfs file system, with the smallest record size that you.

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Can tolerate um because the virtualized environment doesn't really understand.

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On or doesn't deal very well with, usually having a large record sizes.

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There is some outstanding work that I've been trying to push up.

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Into opens the house and eventually to freebsd I'm.

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That allows some.

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More flexibility in choosing the underlying record size: up by.

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Making sure that may be due rights that are not aligned to record sizer art.

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Are to multiple record size: that the.

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The cast doesn't block while we're.

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Doing that we modify right operation but in general.

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On the long-term best practice, I think this was the conclusion that we kinda.

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Came to expect a logic is that damn more visibility you can give to the underlying.

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Guest rd- it's not underlying right over last.

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Yes to the guest above you about the underlying storage.

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Up the better off you are, and so we were exploring actually.

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Some virtualized file system drivers that word.

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Basically, just forwarding the operations.

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Directly to the underlying storage- and I think that a bit so they let me get.

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With rich realizing that file system, rather than for tries a desk.

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Yes, okay, cool, so like you'd, you kinda have like a.

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And a fast typer layer between the guest and the host, rather than to.

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Ice cuz you'd like where yeah yeah so.

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Understanding that the transport between the guest and the underlying storage is.

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Reliable you can make some accusations there and, but also, if you could.

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If you pay per se, but this really is your best, you can you do the things that.

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You do with your past a by actually make it a lot easier for the.

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For the guest, which one a great snapshot, whatever a.

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There are other ways to that which is he said. Well, I skazhi in those types of.

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Protocols but the the fact you're not talking.

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Really directly to what your, what you really do.

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Landing on becomes problematic in and does have two cocks.

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Who waiver request that you told your camera down a little bit, so your head is.

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Further up on the screen, so that are you cool thanks, though we can also your cool you're, a bsc culture.

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I mean I national icons go across the bottom, so.

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Oh, I see so I'm actually wearing this on at a respect for paul chek unveil.

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Who just recently passed away I'm so you may know about this.

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Up this conference actually you're busy 2011 was the first european.

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Econ but I had the pleasure to attend. He made this event happen.

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And basically is responsible for this. The continued success of the europeans.

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D-Conn conferences, and so you will be sorely missed.

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Absolutely- and you know I think, there's no.

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Greater honor in the engineering circles than.

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To have your the things that you created out the view other yourself so.

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I'm certainly quite an accomplishment. Your with the year bc.

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Use the unconference cool so.

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A couple more questions, a.

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So a chip the chip are, you are.

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On the cannot do when asked the question, maybe.

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Yet choose create good on you meet and ask your question.

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Yeah um I was at the open vs conference.

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Left ball and one other thing that caught was the.

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Free now seems to get patches before freebsd.

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Ok, your son, if that's correct, and what the logic behind them.

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Things move around in bst, sure.

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So I'll I don't, I can't say whether that's true or not, because they don't. We.

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Have my paul's directly on bring us, but the way that.

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Things happen in any type of open source community is whoever does the work.

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You make that work, happen and gently.

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Who works on the freenas project for iraq's is one either.

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%Uh major integrators changes that come from a little mouse.

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Down to freebsd and babe, you can have a little bit more color to.

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How that works? Just for my own experience in trying to you.

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Get work that's been developed at spectra logic back into the open source.

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Community oftentimes, when you create a change for.

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A particular varmint say it's free now store a spectra, has spectra pst, which is our platform.

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A there are certain requirements.

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That the open source community may happen don't apply your product, which.

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Allow you to you know, increase the speed which you can.

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Provide a solution for a particular problem.

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But it's a partial solution, right, cfs.

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Is up kind of unique in the sense that the features work.

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Across the board, so if you have deduplication or you're using snapshots.

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And replication- and you know all the different features, raids, iverson's, mirror.

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The the underlying goal is that all the features apply everywhere.

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There are no surprises, no hidden gaps, %uh.

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It so when, when you go to develop a product, though you don't necessarily.

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Have to you still all those gaps, you're, balancing time to market.

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And satisfying a customer requirement or a customer escalation, ready customers.

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Down on so, I think that's the reason why you'll see.

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Different features not quite available everywhere,.

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I'm the one that I've been working for two years, the.

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The a synchronous remark by ray fault, handling for zfs.

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A yeah, it's frustrating to me that it's not.

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Up in the tree yet, but when you go into the work to get it there.

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You realize that the initial work really was it.

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Was a complete enough or wasn't to the level.

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At the open source community expects and.

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So having to go through that process,.

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Provides value to the open source community in terms of increasing the.

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The performance or the quality of the work that makes it up there.

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But does encourage a lie and so will be talked about.

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How to increase their rated innovation and gs, bass.

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And things like that, I think we can do that by.

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Explaining to the community the.

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The work that needs to happen it or you take something that is a.

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A feature in what are the options are one of the commercial product that uses.

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Cfs and to get into the community.

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And try to figure out how to share that that world or I'm.

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In increase the number people who are willing to do that work, yeah.

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And island had a a good point on.

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Rc just saying that you know that a.

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When the code gets into particular repose verses, when it ships.

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Commute to different things rate, so it may be that.

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A given feature arrives in arm.

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Freebsd source code and free, nicer skoda essentially the same time.

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But I you free now, as the shipping were often you may be, there should be a new.

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Release, you know every month, verses on freebsd.

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You know only typically ships every six months or so so.

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I it depends on bike if you're looking at like every this product versus the.

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Source tree no previous, the obviously you can also down the road, the current code and compile it yourself and.

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Run it on, but if you're running a really scratched and that's gonna are.

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Have had more testing applied and also be a little bit further behind.

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It was a you not ready on the bleeding edge, so I wonder.

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If a now you have any code, add on: on.

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You know the most typically does not have branches so.

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Some other features that we talk about will see that it slides or maybe they'll.

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Show up on summer get her on. Is the.

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Which what we do about that to the people can see the work in perhaps.

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Participate and polishing it to get into the.

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That's a good question so on you lou most has a little bit different.

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A with this model than 50 in that there is never this mother.

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Essentially arm, if I the most is like.

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A source code repository and the idea is that all the code in there.

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Is production all the all the time on.

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You know thats church, you varying degrees, but that's the goal.

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On and then are you there is no like limos product rate.

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Just kinda like there's no, the next product on you have to give its.

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Kinda- and I love you with that, like there's the linux kernel, but.

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Though it's gonna by itself doesn't really do anything.

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You have supernova distribution, so lip it was the same way where.

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On different distributions, I like for you well I'm you us worried about a girl, immerse.

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Are colonel and surrounding library, court code.

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And for them to their releases so that they actually do this is.

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Pretty often, I think the they do you like bloody.

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Releases are, I think, every two weeks on.

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So you can run you know very up to date, code.

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From a mess on their I'm in and they have.

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They also have I they do support, and so you can get your long-term supported.

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Releases that you know I don't know those made only be updated once the year, something on.

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So I would say in terms of getting more people involved with.

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New polishing so on, I would say.

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One is like you know, all the supply doing this. You know I put up for review.

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On on on review board and send out an email to the.

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Developer at open decks the best outward nine. This.

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So are, I definitely would love to see more people.

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For just being there and saying you know, hey, you could sucks.

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Or you you know what about this feature? How does the truck with that.

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On you, you personally I'd love to see that.

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0 %uh; okay, sorry, our.

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Sorry, andre on the the you will, hang outs only actually supports.

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Are like nine callers, I'm so.

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I you can watch on. I.

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On the youtube and and give us your questions on irc.

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Its not so are those the look will know from somebody on irc saying that there's.

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There's too many callers on rt on the google+ hangout.

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Into concludes like, were I arm. I don't think it will produce, be more input.

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Reviews on- and you know.

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Even like, maybe soon as you don't have, the quality bar.

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In the most and I getting you to follow patches.

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People see had actually that didn't work on here's.

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You choose how to fix. It will tell you that passion as soon as possible.

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And to can add to that.

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I think it also it you know, as people find like.

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Different teacher sitting out like at hobbs, you know.

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From different companies are, you know.

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%Uh community members: it's a great way for like.

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Somebody who just kinda wants to get started like contribute, they could take.

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What are these things actually start? You know kind of polishing it up and without really having to know a lot of.

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The details, those you know what its initial intent was.

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They can actually get it working and compiled and work in.

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In a truck tested on different beast, 0 up version serve.

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Orchestras as cfs and then you know, put those things up for review, so they can.

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Get ingredients that to actual industry, I'm that would be great.

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Absolutely there's tons a patch is out there that are like.

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A better than other for a long time. You know years.

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I actually just picked up one for that was are the coppery on. It is 2013.

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On and I'm I'm working on integrating it into you.

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I roxx product and then into lamar's.

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On but they certainly number those and if anybody.

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You know has the initiative to do that. I'm happy to send you some links to.

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Other outstanding reviews.

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Slash, you know code that you got sent out by just have a quick.

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Guyana, over the finish line and.

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I had a question on jer it as you. Let guys have been at spectra, have been.

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Looking at like no petabyte scale and the.

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You know, storage, market and technology continues to evolve. What types of.

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Problems have you guys encountered with zfs and kinda the chain gene.

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You know, drive manufacturers increasing and slash.

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You know technologies. What types of things do you guys encounter.

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um That seem to be obstacles as as technology continues, change.

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Right so I could talk about that terms at you're near term, things in.

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It may be, a longer-term outlook are.

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Our car focuses mostly about up correctness and performance.

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So we ran into problems with things like sparing and.

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A couple other minor things inside yet us that.

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Again is an attached said: that's not really complete enough to push ups train.

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But hopefully we'll get there other form inside.

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I think that we've been surprised that the performances in.

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Better than dead- and it is I'm in some cases.

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In our case, the the object typically large.

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We're doing large sequential writes large commercial re, its.

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Especially in in their 80 transform.

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We don't think you're getting a performance that that we should be able.

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To get out of that on, and I think we near a downed some places for.

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Are some reasons why that is the case and they're all you know.

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Cracked or just a matter of finding the time to and.

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And doing the work in a medium-term.

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Continue to have spinning desks p cheaper than flash, because flash has.

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Been coming down in price as lead the storage industry, to really look at this.

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Shingled magnetic recording scheme so there's.

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This kinda technology gap- it's happening right now that fitting dries been using.

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Pmr perpendicular magnetic recording for.

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Got ten years now, 12 years, something like that and they're coming to the end.

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Up the ability to increase the density of the media in that space.

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Up the follow-on technologies, key assisted magnetic recording.

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And bit pattern media. Those are multiple years away.

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On we might see something to tell a 2016, but it's probably.

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2017 before we see humor on and we don't really know what that had to be- is gonna.

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Become available so to.

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Continue the the historic.

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You know doubling the capacity every two years that we've seen in the spinning disk market they're, really looking at single magnetic recording and you can take a.

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Single magnetic recording, as on laying down tracks the same way that would lay down shingles on irish.

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So in pmr, perpendicular magnetic recording.

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You can write you can retract that are narrower than the tracks, the you can you.

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Write so they take that bid on that per the technology, they say well, how could be.

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Narrow the tracks that you're right, the way that we narrowed our biz by partially.

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Overwriting them with the next track, so you can say you can take a bit terms. A you know in terms of logical block,.

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Address is, as your writing, data on.

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You can keep on writing in ascending order, but if you wanna go back.

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And rewrite something that you've already written. Well, then you've got a mess up your shingles right, just like a terrific you, you have a leak under one single somewhere.

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Yet a carefully do something right now: data refer their that.

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Carefully lift up the adjoining shingles in she weren't something in there.

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And there's quite a bit, it expects right to do that on.

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So we already are seeing these drives hit the market.

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And because they they do not allow.

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Arbitrary overwrite, the existing data, I'm.

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They're being priced very competitively to try to entice.

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The rest at the storage market to.

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Adjust to the way that the strikes work today can be used.

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And so typically see like a, I tend to want to order.

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Ninety difference between the cost to flash and spinning drives.

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And if they're actually exceeding not with somebody's.

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Drives that are coming out like seagate's new, a terabyte.

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Archive drive, which is this this as our technology.

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Right now, as a market, you about a 20 percent increase in density.

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I'm at cost kind of complicated algorithms to be able to her.

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Reclaim space in defragment free space and things like that.

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On but the trajectory shows that by 2020.

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Sixty-Five percent up their storage improvement for density improvement.

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From non shingles to shingle mean it's a pretty huge difference right, it's like.

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Lab itachi has a roadmap slides somewhere the show the 23 terabyte.

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Spinning drive with some are, and I think, a fourteen terror I non smr try so.

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For the two large archives, where the data is mostly.

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Rest, the smr stuff- it's here.

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um Its it's going to.

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Be something that we have to adapt you all. The major players are adapting it.

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Are adopting it and are you talking about pushing it into you? There.

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Enterprise-Class storage, what place you can see this right now is, if you get.

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Say: hitachi a terabyte, a gillian dry.

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Initiate they actually use the same technology that the use for single.

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Magnetic recording to deal with this inability to overwrite data.

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To accelerate red rights, sony outer tracks.

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About particular drive are zones that are reserved for the firmware.

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And they have use a lock structured system to take random right to make them.

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Look sequential and it sometime in the background they pushed into the main store.

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Now, on that, drive to main store is a traditional store.

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You cannot overwrite sectors as you will, but.

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On because they already had this technology, they were developing for us.

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Mr drives, they said well gosh. We can make random, writes way faster on these.

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Slower spending drives so the technology is.

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Is going to be there whether we like it or not? So what is that the person you're.

B

Fast, I I think it means trying to figure out how we can.

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Get around the difficulty that cfs has hit moving data.

B

And I'm that little bit more for the route.

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In the near term, we have just understand the algorithms these drives are using in.

B

Order to emulate the ability to operate data wherever it is.

B

And the way they do that right now is.

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On they will perturbed as the fs zone, people right to the middle is.

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A ics panetta marzo their right to the middle other and then.

B

When they get to a point where, on the host stops providing data.

B

They do that like a track before I'm. So when you, when you write middleton st marys own.

B

You basically invalidate about tracks worth a existing data.

B

About the place where you're at., so they.

B

They basically will take a stream, a sequential writes in assay.

B

0 look you've given me at least two tracks were two tracks were 33 tracks.

B

Where the data I will write those in place and then I'll take the area that would have been.

B

Interfered with- and I will push it over to.

B

To this private drive space area to eventually.

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Be rick I'm push into the main store when.

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Garbage collection in free space, %uh reclamation can occur.

B

So that's a prolly, very confused explanation.

B

How system are works in and the the complications of it.

B

But I think in the near term up what will end up doing inside the a press.

B

Release think specter's looking at are making sure that the right things in ascending order is it.

B

As mr. drives appreciate that I'm.

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Perhaps making sure that the way to be account for free space.

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Aligns with the zones that are in smr drive.

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On and then also looking at.

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Ways that we can aggregate data better as we write it.

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And make sure that in incomplete order to the drive can see that we're writing.

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More than a track it online and it cannot wait what's effectively a double right penalty on these trust.

B

A

Linda, I guess for sex just.

A

Alan, I know you had a you. You wanted to talk about, smr stepped it up.

A

The just an address year, the things you wanna talk about. Smr did you have any.

A

Follow ups are the key covers most. It was just.

E

Wondering you know: is there anything special to do in service to be.

E

Are more compatible with smr, like in most cases at office, doesn't override everything in place.

E

So really doing are.

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Due in part to the fsa get over it in place at the labels for the.

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Turrentine for the through burglary sucks, I either.

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Anything we can do are so to manage.

E

Smr and make said office worker that kinda.

E

Very nice weather I had a similar survey question.

F

Sorry for jumping in I'll I we noticed.

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A couple of us were looking at sr: martin howard.

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Relates to zfs, and we concluded that the hard part.

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Isn't actually say to labels and that stuff, but.

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Are the thing that makes cfs awesome, repair.

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And that certain that that self-healing, which can cause a lot of render I'll.

F

Some anyway justin few yeah.

B

I think that when people, because the fs their dear.

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They're thinking gusta copyright file system in so you don't really over right.

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Place things like that, but you gotta three blocks eventually right.

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And as you're sending a file.

B

The men data for changes on large swaths a better day to.

B

Change as you extend the file, he had police on the leading edge up the tree.

B

You can take up going all the way back up to the router, the filesystem, so you.

B

Leave in place, you know this paper enough free space. That's in these shingles owns that.

B

Has a son how be reclaimed, and so I think in the near term,.

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If we're smart about tracking the fragmentation of the zones.

B

So that we know whether it makes sense to try to have the driver or.

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Worry access them, so the drive will do cleaning at that point. On.

B

That's one avenue also making sure that.

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Maybe we classify data in terms of its size and is expected longevity.

B

So that we had that freeing stuff, I'm.

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Things to get free rapidly,.

B

You may be at the top of the file system that are changing all the time they.

B

Might be place someplace different than the meta-data thats related to.

B

A file object that a user laid down, I'm.

B

But I think longer term, if we really want to get the best performance at the.

B

System's anyone have access the cheapest drives as the drives that have.

B

No emulation for direct access.

B

And single sector over right will have to do things at the lower levels. At the.

B

Upass to be able to deal with that, the the strength in cfs has.

B

In this area, a lot of other filesystems don't is that it really does combine.

B

Not such deposits to write me calling it is it about file system, I think, is.

B

Modesty, I think, by the people who created cfs.

B

Because you have to rate transforms, you do have.

B

The volume management- all these things are combined into one software stack.

B

So that you encounter a problem, I guess mr., you can basically look at the whole.

B

Thing and say how do we solve this was the right way to solve this. I don't have to worry about underlying volume manager.

B

Changing the geometry of from under me, zfs controls, the geometry controls all the free space management.

B

And so up weather is.

B

Smr or another technology that has to be talked about her, these.

B

Variable capacity drives where, depending on.

B

The yield in a factory that day, you might get nhra driver a quick bite. Your.

B

Bike driver attend, terabyte drive a. I think that we have.

B

A it's gonna be hard, it doc, iraq. It can be hard, but we have tremendous.

B

Flexibility, because, at that nature, up this software stack be able to.

B

Do things with that technology that other people will have.

B

Even more difficulty dealing with cool.

A

Thanks, I'm- and I I think just have to address your.

A

And a specific question about reese overrun smr.

A

On I think I totally agree that could be.

A

Really that on because there is over, you know, he goes kinda been.

A

Logical by all of that order.

A

Rates like kinda go through this pile then get the next found. Those box could.

A

Be scattered all over the are all over the desk on we prolly.

A

What you to make that really work? Well, we would probably need to do something.

A

Like sequential reads over on, which would a you know, which we were thinking about for a long time,.

A

Hear it all, it would also be tremendously helpful for.

A

Of things like crazy, where you know your may be a really wide range, the.

A

Yep, you know even today, like dozens of terabytes.

A

In one reads, the group on: do it mystery not by do random. I ops.

A

Takes like essentially forever on.

A

So you, when they do that we've had for putting on for a while.

A

Is to do you special ruth liver by a.

A

Essentially, like reading in all over the block, winters.

A

Sorting them by the disc offsets an enduring the resolver.

A

But ordered by discuss thats on you know if I would be a little bit early read.

A

All %uh the walk winners, but your problem because you do have no.

A

Of memory, but you could like essentially scan all you read all the meta-data bring in you all the block. Winters.

A

From you know of says euro to you know.

A

100 gigabytes governments can fit in memory.

A

Reserve for that then scan all the book. Winners again find all the ones that are.

A

In the next you talk about 100 bytes then refer those in order, I'm, even though you have to be that would involve.

A

You're reading the metadata multiple times, but it still may be.

A

Overall, much faster than on you know.

A

During the round, my house, I even know even ignore asmr.

A

I'm even just on these really wide reads the group that people use.

A

And there are other alternatives to rate so.

B

If you know that, for instance, the drive is a brand new drive.

B

That it's not like you to go to the you, can do it a really small result for.

B

I'm you can look at the free space maps you can use. The free space must be able.

B

To do you are something that doesn't require you to go through all the medical well into.

A

Folklore, so if that's true, if you're using me re.

A

On so, if you're using me reading, then you could go to the space maps.

A

And find work, parts are located in the news copy, just added a.

A

In order on the credit cedars base maps different on that.

B

The yessir, your effort for raizy the the problem actually.

A

With reviews that the on the space not.

A

Essentially is talking about the whole reads: the group.

A

On as a whole, with offset essentially going round robin so like of that, one is.

A

On what one of the two is on disc two upset, there is I'm.

A

Disc four and then back to this one so on.

A

The problem is that, given the space, not we don't know where blocks.

A

Actually begin, and in so we don't know where the parity is versus, the data.

A

Over giving abuse block on this comes, this is an issue that comes into.

A

Device removal as well, which is why it's right on top of my head.

A

Yeah um so changing years.

A

A little bit other than the you had a question about.

A

Actually, maybe not to you that much about kevin reese over.

A

A

I don't think I can I'm youtube, you can change their your.

G

Okay at home so- and I do a lot with the freebsd and there's a couple throttles.

G

In the early, the comp delay eastern us governors summer, at least.

G

Sheesh, I'm really intrigued by those I think, there's a really cool.

G

Sheesh, I'm is anybody working on something like that? A.

G

Over is it even possible to do at adidas? At my whole,.

G

And that would be %eh architecturally. That would be so cool to be able to set.

G

Some sort of prior nation at sheesh at a dataset ray and saying.

G

She, you know, put a little for a little bit a delay in 20 the irs for this.

G

Dataset arsonist in a separate I'm not I. I really don't know how that works in the.

G

Freebsd the hash, the delays that they have on screen re so gross.

G

Scalp and justin yeah, so the curtain hooks the sea inside freebsd. I think our.

B

Little outdated, maybe georgia's a better person to talk a little bit about how.

B

Changes in the underlying I a scheduler have.

B

Impacted scrubbing resolver on.

B

Because the way that it has worked historically has been kinda like is that.

B

As a hammer like you know, I'm consuming too much bandwidth so.

B

I should go away for a while on and I think we have better tools now.

B

To be able to do that, riding down the aisle scheduler at the bottom of the.

B

Stack as a matter fact I'm for a hackathon project in a carer which one.

D

I I started some work in a serious, actually removed. Those troubles.

D

To allows the I'll schedule it actually.

D

Do more the work and, in some cases, do sum up what we were talking about.

D

Earlier tom, about trying to make this more sequential arm.

D

The next step for this project was sort this hackathon.

D

A work was to actually allow us to differ, allocating memory, so we could.

D

Even issue you know thousands a bios and not even consume memory.

D

It to you actually need to do that reads: mosser, that work is done.

D

But I think linda what you're looking at the correct me if I'm wrong is your.

D

You're kinda wantin, almost like a quality of service, her dataset, which is something similar to.

D

What the folks at joint implemented for zones on it it they have.

D

I'm kinda throttle on a persone basis, so it's not as granular status at.

D

Am but allows you to kind of give.

D

More shares to some zone over another one.

D

I'm that work, I think, is out. It gets another weathers that.

D

Like patches, that's probably sitting out and get help somewhere.

D

That is just needs to be pushed over the finish line into probably be.

D

Enhanced or made I more generic to actually work on a dataset level cross.

D

Css, you know, can take take those concepts and just make a generic across the fs.

D

That's fantastic.

G

A

Cook so um ii. Don't me mister.

G

And myself asking questions, yes sure go ahead than that and.

G

I had I had one more, I'm I'm is anybody working on our? Are there.

G

Now that I know that how to accept the army actually go.

G

Stick my fingers and match, and but it and other projects and I'm like an.

G

Empanada to take a lot of systems around, like the unt large files show and.

G

You know kinda wanting to take each and I'm it.

G

Take cash dressed kinda that next level I'll shte.

G

I'm you know, maybe a full ssd cool thats.

G

Out replicated back to us, they needed school.

G

And best leave leave some pain.

G

On the the primary pool to its the.

G

The filehandle lunch meta-data something out there.

G

And I did during it really analogously right now with.

G

And no with a fine in a mooch and each.

G

And the missing link back and each and.

G

But is there anybody out there working on anything more elegant around like.

G

Cheering on which being able to you know, take hikes.

G

And hotfile sandwich keep an eye on.

G

On faster desk and and tenant moves to.

G

Back sounded, there are a couple things that I'm aware of.

B

Nom that are not for, I think, generally available.

B

Gears on not this early for hot data, but for tearing.

B

There some work the panzer has done using the additional block, pointers.

B

At the fs allows you to today no option. We keep.

B

For data to be able to reference different locations for.

B

That day, a well upon location might be in a local ssd.

B

Another one might be in the cloud another one might be added some.

B

Some corporate office somewhere says the cancer thing.

B

%Uh, I believe the changes are fairly.

B

Invasive disease fast and may not work.

B

Across all the different features, so I don't know if it works across nashotah.

B

Deduplication or whether you operate your american things like that.

B

I'm also where up some work, that next letter has done.

B

That allows you to you, %uh shunt,.

B

Many data for a cool to a different year, but I'm not aware.

B

Anybody who's doing things like being able to based on.

B

Use job hit rate things like that to be able to migrate data.

B

Between tears and that comes down to.

B

You know the similar areas where, like.

B

Smr is challenging or free space defragmentation.

B

Your file defragmentation, is difficult to see a fast, and that is that the.

B

Office tries really hard to make sure that when you go to access a piece of data that it is exactly the daily, what.

B

And the way it does, that is by these her call.

B

Checksums, which means only move something well, that's the same thing is.

B

Invalid in that area, right, you have to update on find.

B

An update all the places in the file system on that date, as reference not be.

B

Able to do that so you're, not alone. In wanting those features, I.

B

I've heard at several times for that act. Spectra logic is well.

B

A I don't know anybody who has the.

B

Has devoted the resources to try to solve that problem right now, I'm.

F

I would like to chime in you mentioned on, except that work.

F

Meh I work at nicks and assign, I know a little bit about.

F

About that om, their.

F

Like like, on several occasions, you said companies.

F

Implement with the need and whatever t don't need the skip.

F

Because its research question, I.

F

You can get the pics and a coat on get her and.

F

That gets you to the curing to jump the meta-data.

F

Off to the side add to it special device a there is also code for write cache, which is sort of a break back cash.

F

And in the background, the data gets moved to.

F

To school, slower devices I'll.

F

Their is another code.

F

That it does work, I don't actually know how well it works.

F

I'll the code is out there. That's what I wanted to say now. If you can.

F

If you can make you so that good luck.

F

Omg I it did, you know cases.

A

Using news features in their in there actually supported products.

A

I don't I don't know which ones are actually enabled.

F

Into currently shipping product I've been around at nicks and therefore, when.

F

Here high and has been focusing on the latest and greatest.

F

I am, and of course we had to have some changes.

F

At me want to commit, I am.

F

What was the other thing I was going to say about this on your mileage may wear.

F

It and they re on I'll.

F

Our member and and speak up again who.

A

I would think you we're closing in on about 15 minutes left the.

A

The office hour on I wanted to get this one in, for you.

A

Justin I, what are you might work future.

A

Were intense as the fs are, you must are looking forward to.

A

That that is kinda in the paper. You know that and then.

A

You, what do you think is most sorely lacking. I in zfs.

A

You think someone possibly yourself.

A

Possibly someone else should get you going from a yeah. I think im.

B

What am I looking forward to you? Others will send receive.

B

The we definitely joy specter, you talked about.

B

Enabling replication for our customers for some time.

B

And on the problem that we have the existing customers that want this.

B

And they have, you know terabytes to petabytes for the data already.

B

Set up and have a loss you think going somewhere else.

B

And so previously tell the customer don't sneeze.

B

For two weeks right up, so I think.

B

A definite looking forward to that and I think that the solution to its really.

B

Elegant so ok I'll be really cool um as far as most sorely lacked.

B

Feature, I think it really depends on the the people that you ask me. Some people say.

B

Things like I'll governor whitman, they would. He have my own. You personally.

A

But my buddy yeah, um I with modesty.

B

A cluster z, a passive some sort, and was that, from from my previous, the.

B

Perspective where we don't really have a good clustered solution.

B

Previously, what it is you know, literally licensed in such.

B

And I would love to work on something like that.

B

Com, I think, there's some some other.

B

Things that police for the free bc community you up smaller features that.

B

People are looking for two like on at spectra logic. We have the fst.

B

Which is a fault management even for zfs? My personal opinion about the fst and I.

B

Could say this because I wrote close to that is that it's a stopgap solution, but people still need that does features right. We on freebsd, we don't have the.

B

Full fault management framework the seattle limo send on some other operating.

B

Systems and those the fst was awaits you it. The scandal.

B

The faults that the majority people using zfs would encounter.

B

I'm there are a few things just like.

B

You know, as we talked about her, has come up several times during the session.

B

There several things about the st. in the things that it requires colonel.

B

To prevent it from being up strange, but hopefully sometime this year.

B

Knock on wood will get that up there on.

B

There been a time means that um it would have been really nice or would be really nice to have.

B

A a pathway to do things like free space, defragmentation.

B

Or object defragmentation, I think, there's still a lot of low-hanging fruit.

B

In terms of initial data placement that that makes more sense to focus on initial data placement.

B

Ntfs and and allocating a.

B

More resources to the allocation, algorithms, the a pass-first.

B

A so I don't think that is as pressing this summer. The other things.

B

But and then there's this the.

B

You know this. This fear that I had about smr.

B

I think that will get worked on.

B

I think there are enough people that are similarly scared about the performance.

B

Drop you get if you don't do anything with a smart rights that some work will happen there.

B

Followup question on smr.

A

All filesystems are evaluated.

A

In comparison to the best alternative, so.

A

Do you see the competition.

A

Such as it is in the filesystem space.

A

Also very concerned about smr and doing any work in there.

A

Do you know any other filesystems that are working on optimizing stuff for smr.

A

Or the only work that I'm aware of is.

B

What's been done by the drive venders, so you'll see patches out there for like ext4, but they will acknowledge the fact that if you run ext4 on top of.

B

Any type of volume manager it doesn't work.

B

I don't know, I think that most of the the first place you are going to see real smr.

B

Support in production, apart from running on devices that.

B

Emulate a normal disk drive is going to be a cloud vendors.

B

You know the googles, the facebook's things like that, where they're basically.

B

Just putting resources into you, okay, if you start today- and you want to do an object, store.

B

You care about snapshots, don't care about replication, ok about his ethics.

B

Anyway, do it on the cheap drives, how to do it, as I think you to see papers.

B

You know this year next year about how people have done.

B

Object stores on top at smr, but.

B

If you really arm, if you really.

B

Want to take advantage the compelling features that cfs hatched. I don't look.

B

There is a competitor right now that is as mature on really as well equipped to be able to deal with these challenges. I'm in for me.

B

It's the mature maturity par, you know, being able to take a product.

B

Idea and develop it on top is your fast.

B

And not ever lose any customer data me that's.

B

You can't do that with the competitors. You know they're, just not at that point.

B

Yet, and so long as as a community, we could you develop our stuff with.

B

That level operator, I think that.

B

People won't be able to catch up minutes its. I don't get. It estimate for.

B

The number and yours that, when it is your best, but it's a large number and.

B

It's hard to think I've. You know starting from scratch and get the same.

B

Features in the same reliability was something else yeah I mean.

A

Definitely more than a hundred engineer years, yeah, I'm.

A

And so it sounds like this: is it really an area that is the fs.

A

A has the opportunity to paul had a other.

A

General-Purpose filesystems, you know, probably did the.

A

The hugo is new, with respect to the world are not going to be making.

A

General-Purpose file systems with snapshots inc on all that stuff. You know.

A

They're gonna any this heritage that they need their name from at some way way higher level.

A

In the sack yep, it's actually my understanding that the linux.

F

Filesystem community, I syrup fuels.

F

Indifferent about a similar, as in server.

F

Well, it sounds like a good idea, but we don't see a compelling.

F

Use for general purpose storage, aside from just.

F

It's cheaper but it makes everything harder. So, let's see if.

F

This is just a fad or, if, if it actually is.

F

Around to stay so, let's just sit back and wait a little while.

F

You would know about, I think, that's wishful thinking.

B

If you look at the cost curves and the capacity.

B

Density curves, they can't updating the disc industry.

B

They can't keep their current for.

B

You know they near march without, as a mark.

B

And so a we even did hear that.

B

The enterprise-class trust you know that the 10 change a tk rpm drives.

B

Are good at bring this technology yet so.

B

You may bet on on flash totally displacing.

B

Spinning media in in these tears, perhaps.

B

Because cheap enough, but we seem to be.

B

A society that generates so much data that.

B

Flashed just isn't the solution for everything it just can't be.

B

You can't get so and matt real, quick just to follow up on me. Outbursts.

D

Filesystem some are question I ran across as the other day and I have not had a chance to.

D

To the into it, but there is apparently somebody is working on it. Smr specific.

D

File system called hi s. Mrs s, I think it's probably more research than anything else, but.

D

D

You know there are people that are looking at this as a way to address.

D

To issues that are some are going to bring the surface, who.

A

Cool on so wanted to get in one.

A

Last question for you: so it think justin, you've attended.

A

All %uh the open, the best developer summit, all.

A

Fewer 3, we also got better ones. I think you could tell in europe.

A

Yeah, that's true: we had the one in your opinion. What and another one coming up.

A

In europe on so wanted to ask you what what would you like to see more.

A

I in the next open the festival, personal network, which we're.

A

Hopefully we don't have a firm date yet, but we're looking at.

A

I october 2015 on.

A

Which'll be very very close to the 10-year anniversary.

A

A when over the bus was when's, the fs was first open source.

A

By sun microsystems were so a.

A

We will have a little celebration for that, but.

A

When the your take on where you'd like to see.

A

I, moreover different the next developer summit.

A

Yeah, so I think that on my.

B

My thoughts on this kinda mayor mirror what.

B

Previously is looking at doing four sum up its developer summits.

B

And to historically there's been.

B

You know presentations, discussion and things like that and then having a.

B

Second day worried you hack it on.

B

I would we like to encourage people to think about the project's.

B

And what progress they can make.

B

In person that he can't make otherwise and try to.

B

Up push those ideas forward and get slots.

B

Into the open zfs you, the hackathon or.

B

Or maybe even a a working session or open discussion session in the main day.

B

A conference because it really is that face to face time.

B

Where you have access to a whiteboard and free-ranging discussions and things.

B

Like that, where you can make you know it happen, are you can make more progress that you.

B

Can make in a month or two um so me historically, that packet on stuff has been.

B

In terms of you know, what can you mostly get done in one day.

B

But even when you talk about things like a.

B

Channel programs right that a as a multi-year effort.

B

And things like that.

B

People in the same room to talk about those kinds of things and how to push.

B

Forward or solve the problems that individuals working on them haven't been able to sol. That's the part that the.

B

Real-Valued I get out a bit up to being able to promote work that.

B

And and organize more than ants, I did you get.

B

I'm perhaps even better attendance if.

B

Some other stuff is on the hackathon days is talked about in.

B

Understood before you so do some kind of like design.

A

Design sessions or something a during the mean day.

A

Yeah and and have a maybe even opened the design discussion for some of those.

B

Things before converts so that people can prepare, I get some other stuff 3, I'm just beat my own experience in trying to come to steve has the best works. Other.

B

There's a large learning curve and so to be able to participate in the area.

B

The filesystem I haven't really spent much time in. I would agree that code.

B

Hansen on be able to participate.

B

Not just to be able to sit there and soak up, you know, which is also good.

B

Right, learn from all these other people. That are the reason why you're there, but.

B

I think to make the best out on best use that time.

B

It's really to prepare for.

A

Who on so, I think we're just about.

A

Other time with justin for what I know why we call them.

A

Office hours, I guess it's one hour at a time- it's one hour, but on this.

A

A role as the hours they had one here in our having.

A

An office hour this year, so there office hours.

A

Don't feel too good ahead, professors and college. You do the same thing with you.

A

Maybe maybe this is the the open, the fs office, our.

A

With justin gets all right now after the fact that nobody will know that, I made a.

A

B

Watch everything you have like these great graphics and things like that. Zoom.

B

In from a double check, real said, unfortunately, my specialty is not.

A

A motion- graphics, yes, call.

A

Well, thanks love, justin comment. Thank you again, linda for organizing this.

A

On hope, lou I, with your help, we will have these.

A

On a more frequent than annual basis.

A

I think originally the goal was scored early. I I think that.

A

That so a good goal on so hopefully look for.

A

I had something going out next quarter with the different.

A

A special host such guest miss those greater.

B

Is low but thanks.