This sounds quite cool. Although it doesn't say so, I imagine the name is riff off Hypothesis, the testing tool that performs automatic test case simplification in a general way.
Is something bugging you?
11–20 of 438 posts
Re: Is something bugging you?
#12The writing is really enjoyable. > Programming in this state is like living life surrounded by a force field that protects you from all harm. [...] We deleted all of our dependencies (including Zookeeper) because they had bugs, and wrote our own Paxos implementation in very little time and it _had no bugs_. Being able to make that statement and back it by evidence must be indeed a cool thing.
I have proved my code has no bugs according to the spec.
I do not make the claim my spec has no bugs.
Re: Is something bugging you?
#13Re: Is something bugging you?
#14Sounds a bit like jockey applied to qemu. Very neat indeed. https://www.cs.purdue.edu/homes/xyzhang/spring07/Papers/HPL-...
There's indeed a connection between record/replay and deterministic execution, but there's a difference worth mentioning, too. Both can tell you about the past, but only deterministic execution can tell you about alternate histories. And that's very valuable both for bug search (fuzzing works better) and for debugging (see for example the graphs where we show when a bug became likely to occur, seconds before it actua…
I assume deterministic execution also lets you do failing test case reduction.
I've found this sort of high volume random testing w. test case reduction is just a game changer for compiler testing, where there's much the same effect at quickly flushing out newly introduced bugs.
I like the subtle dig at type systems. :)
Re: Is something bugging you?
#15This sounds quite cool. Although it doesn't say so, I imagine the name is riff off Hypothesis, the testing tool that performs automatic test case simplification in a general way.
(I’m an early employee of what was, on my start date, just called “Void Star.”)
As I recall it, the name meant two things:
1. Our “autonomous testing” approach is the opposite, or the antithesis, of flaky and unreliable testing methodologies.
2. You can think of our product as standing in dialectical opposition to buggy customer software, pointing out its internal contradictions (bugs) and together synthesizing a new, bug-free software product. (N.b.: I’ve never actually read Hegel.)
We did note the resonance with Hypothesis (a library I like a lot!) at the time, but it was just an added bonus :).
Re: Is something bugging you?
#16The writing is really enjoyable. > Programming in this state is like living life surrounded by a force field that protects you from all harm. [...] We deleted all of our dependencies (including Zookeeper) because they had bugs, and wrote our own Paxos implementation in very little time and it _had no bugs_. Being able to make that statement and back it by evidence must be indeed a cool thing.
I have proved my code has no bugs according to the spec. I do not make the claim my spec has no bugs.
[deleted]
Re: Is something bugging you?
#17I wonder if they are working on a time travel debugger. If it is truly deterministic presumably you could visit any point in time after a record is made and replay it.
Re: Is something bugging you?
#18This looks to be an incredible tool that was years in the making. Excited to see where it goes from here!
Re: Is something bugging you?
#19Reminds me of the clever hack of playing back TCP dump logs from prod on a test network, but dialed up. Neat.
Naturally I’d prefer professional programmers learn the cognitive tools for manageably reasoning about nondeterminism, but they’ve been around over half a century and it hasn’t happened yet.
What’s really interesting to me is that the simulation adequately replicates the real network. One of the more popular criticisms of analytical approaches is sone variant of: yeah, but the real network isn’t going to behave like your model. Which by the way is an entirely plausible concern for anyone who has messed with that layer.
Re: Is something bugging you?
#20I wonder if they are working on a time travel debugger. If it is truly deterministic presumably you could visit any point in time after a record is made and replay it.
No comment. :-)
Disclosure: I am a co-founder of Antithesis.