Oh! Gosh, yes, that DOES explain it. Somehow I had it in my head that both RU and RC mapped to SI, and RR & Serializable mapped to SSI. That's the case in YugabyteDB, but not here!
I'll also see about getting a version of these tests that doesn't involve ON CONFLICT, in case that's relevant.
--Kyle
On Sun, May 31, 2020, 23:56 Peter Geoghegan <pg@bowt.ie> wrote:
On Sun, May 31, 2020 at 8:37 PM Kyle Kingsbury <aphyr@jepsen.io> wrote: > This looks so weird that I assume I've *got* to be doing it wrong, but trawling > through the source code and pcap trace, I can't see where the mistake is. Maybe > I'll have fresher eyes in the morning. :)
READ COMMITTED starts each command within a transaction with its own snapshot, much like Oracle:
There cannot be serialization errors with READ COMMITTED mode, and in general it is a lot more permissive. Probably to the point where it isn't sensible to test with Jepsen at all.
It would make sense for you to test REPEATABLE READ isolation level separately, though. It implements snapshot isolation without the added overhead of the mechanisms that prevent (or are supposed to prevent) serialization anomalies.
