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Comment by zenithm | Hacker News Reader

Welcome Dan.

What other production implementations of Calvin are out there?

I said in my post: "influenced the design of several modern “NewSQL” systems" --- I'm not aware of other production implementations of Calvin. But VoltDB's command logging feature came directly from Calvin. So basically I had in mind FaunaDB and VoltDB when I wrote that sentence. Neither is an exact version of Calvin, but FaunaDB is closer to Calvin than VoltDB. Obviously, the Calvin paper has been cited many hundreds of times, so many of its ideas have made it into other systems as well.

> But VoltDB's command logging feature came directly from Calvin.

VoltDev here. Huh? We added this feature in 2011 and read the Calvin paper sometime later IIRC.

"The case for determinism in database systems" paper (which described the technology that became Calvin) was written in VLDB 2010. At least one VoltDB developer told me that command logging came from a talk we gave about this paper to your team.

I think they happened independently, but it's long enough ago that I might not recall if I or Ning had inspiration from somewhere.

If you heard it from Ning or myself then it's probably what happened.

Yes Ariel, it was you who told me this! But I agree with jhugg that it was an obvious choice based on the VoltDB architecture.

lol

I think that logical logging was an obvious choice given VoltDB architecture. It's totally possible there was a talk that was involved for somebody though.

That said, we <3 determinism at VoltDB and rely on it to achieve what we achieve.

How does Volt's transaction resolution mechanism compare? It sounds like that would be a third model yet.

We have a whitepaper here: https://www.voltdb.com/wp-content/uploads/2017/03/lv-technic...

My brief summary comparison. VoltDB is a bit less general in some key ways. It tends to have the same performance no matter how much contention there is, which is rare. It's also getting pretty mature, with lots of integrations and hard corners sanded off.

It also typically has much lower latency than these systems, both theoretically and practically.

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