Agoric Office Hours, 16 Aug 2022

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From YouTube: Visual Debugging in the Agoric VM - Office Hours (Aug 21, 2022)

Description

Dan Connolly, Software Engineer at Agoric, reviews efforts to apply the Causeway visual debugger to log files from the Agoric VM. This clip was recording during Office Hours on August 16th, 2022.

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A

Hi everybody, dan and company we're doing office hours at gork and we got some questions on swing set um and you know what's going on with the messages in our system, and we want to look at there's a thing called causeway, um no cosmo visa. We talked about that earlier.

A

Okay, so there's a pull request of mine from a long time ago. It's kind of in the background here we are so causeway is a one of these time, traveling debuggers from quite a while ago.

A

um Let me see if I can just find that.

A

uh Introduction.

B

A

Distributed debugger there's supposed to be a video in here somewhere some pictures anyway,.

A

Oh, look at that sort of still runs.

B

A

So this is one of their examples.

A

I'll try to get a better overview here. We go.

A

A

So the idea is, you have all these vats running all over the place and you're like what's going on.

B

Yeah yeah yeah ethanol question so.

A

um The messages get what this does is it instruments the calls between vats, um and then it allows you to see how you got to in any particular place. You know any particular call what was the cause of it um and they guess. I guess they do visualizations like this, so you can have.

A

I guess this is guys like it's not exactly this example, but there's the example of you know, buying a plane, ticket and and getting a hotel, and you know certain parts of that can go in parallel, but then they have to join up and stuff like that.

A

So this is the history of it kind of goes back. I don't know when was you know it's probably in the 90s or something like that? So um then I tried to convert slog files into the format that this tool eats.

A

I had some luck with that.

A

A

Where's, the actual code- let's be here.

A

um Let's see what was the last question, you asked.

B

uh What what tool uh you're using the output for or how? How can you visualize it right.

A

Right, okay, so.

B

Fixed with it I mean I was just looking only on the text, representation of it.

A

Right um so this picture has got these calls, and it's saying that okay, this is a call to kernel, object, 31 and the method is get sharing service, and this says that the arguments are that long. It doesn't actually tell you what the arguments are no, but in some cases they're very large. So this is saying basic. I think kernel object. 45 is probably zoe. Zoe install a whole bunch of stuff.

B

A

A bundle um so, but this doesn't tell you um another thing: that's on this arrow is and by the way, when you're done, here's the kernel promise, for which please give me the answer right, because then you'll see this kernel promise fulfilled.

B

A

What actually allows you to say, oh, that that installation turned out to be you know and then whatever gets fulfilled at colonel promise, blah blah is the result of this call exactly that would be the installation, um and so that is where this I was. I was doing it. This so call is in this diagram right now, but not the arrow in the kernel promise. So this would allow you to say.

A

Oh, this call is going to get resolved with that, and then you would look at this later in the diagram and say: oh okay, that's how it got. You know that was the answer to that.

A

So that's that's a! I guess. Sometimes I had it shown in this diagram and sometimes not because it got too busy or whatever.

B

Uh-Huh, okay yeah. I I kind of I kind of figured that um it goes together in this way like what was uh what was uh called and uh what was sent back. uh I was just wondering if, if there is a tool, I can actually use it for the visualization that you that you showed us.

A

Right so previously, so.

B

So I will take a look at that, probably as well, because it it looked cool yeah.

A

Right so um yeah on good days.

A

You know this thing allows you to look at.

B

A

Of the things that are going on and how they relate- and you know the the different colors are for different vats, I believe- and so this is basically this vat was calling that map and when you click on it, you get things like.

A

A

But they actually have the whole stack, trace and stuff.

A

So if you click, what is this?

A

um Maybe I don't? I don't see the stack trace information, so it would actually show you the the source file and the line in this in the source code where, where the call happened and stuff, what is this telling us.

A

I can't read this anymore. I.

B

Once knew how this worked.

A

um There's also a video somewhere in the causeway world that is good for orientation.

B

So the output file should be just input for the for the causeway tool.

A

B

And that should work, okay,.

A

There it is right, okay, so, um as usual I'll give all these links um but uh yeah. So this is the a good you know, four and a half minutes to tell you which ended.

B

Up awesome, awesome yeah, I just I just needed. I needed a pointer. I.

A

B

I'll I'll manage the rest. Thank you very much.

A

Yes, if you managed to get more of that working, you would get many cheers from the dev team.

B

All right all right, well yeah, if you, if you're looking into this lock file long enough, you'll start seeing things.

B

The question is: if they are real or not, I sometimes doubt it.

A

Yeah um yeah, I was doing in our incentivized test net. I was loading them into like pandas and doing visualizations. That way and google big data, and I was doing all kinds of weird stuff with them.

B

Yeah I would like to, I would like to actually later see uh uh a test net or devnet's clockwise. If it were at all possible. uh I mean, I think nick told me that I am I I can ask for that, but I have never done that so far.

A

B

I figured I figured it would be way too confusing to start with. So I was just.

A

B

Yeah, that's okay, I'll I'll I'll! Let him know and ask him if it's if it's possible, if it's okay and we'll see.

B