Comment by aphyr | Hacker News Reader

Comment by aphyr | Hacker News Reader

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I'm not sure. I've worked on a few projects now which employed simulation testing and passed, only to discover serious bugs using Jepsen. State space exploration and oracle design are hard problems, and I'm not convinced there's a single, ideal path for DB testing that subsumes all others. I prefer more of a "complete breakfast" approach.

On another axis: Jepsen isn't "trying to get there [to FDB's testing]" because Jepsen and FDB's tests are solving different problems. Jepsen exists to test arbitrary, third-party databases without their cooperation, or even access to the source. FoundationDB's test suite is designed to test FoundationDB, and they have political and engineering buy-in to design the database from the ground up to cooperate with a deterministic (and, I suspect, protocol-aware) simulation framework.

To some extent Antithesis may be able to bridge the gap by rendering arbitrary distributed binaries deterministic. Something I'd like to explore!

This is a super interesting distinction and I'm glad I wrote my superficial drive-by comment about FDB's testing to prompt you to make it. :)

Has your opinion changed on that in the last few years? I could have sworn you were on record as saying this about foundation in the past but I couldn’t find it in my links.

I don't think so, but I've said a lot about databases in the last fifteen years haha.

Sometimes I look at what people say about FDB and it feels like... folks are putting words in my mouth that I don't recognize. I was very impressed by a short phone conversation with their engineers ~12 years ago. That's good, but that's not, like, a substantive experimental evaluation. That's "I focus my unpaid efforts on databases which seem more likely to yield fun, interesting results".

So, will we get an evaluation of FDB one day? Pretty please? :-)

Apple is positively swimming in money! They could pay me! (Hi, Apple ;-))

Fair enough.

Looks like it was an offhand tweet from 2013: https://web.archive.org/web/20220805112242/https://twitter.c.... I got that from a comment on the first Antithesis post on HN, https://news.ycombinator.com/item?id=39376195.

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