Re: xid_wraparound tests intermittent failure.

On 2024-07-22 Mo 9:29 PM, Masahiko Sawada wrote:
> On Mon, Jul 22, 2024 at 12:53 PM Andrew Dunstan<andrew(at)dunslane(dot)net> wrote:
>>
>> On 2024-07-22 Mo 12:46 PM, Tom Lane wrote:
>>
>> Masahiko Sawada<sawada(dot)mshk(at)gmail(dot)com> writes:
>>
>> Looking at dodo's failures, it seems that while it passes
>> module-xid_wraparound-check, all failures happened only during
>> testmodules-install-check-C. Can we check the server logs written
>> during xid_wraparound test in testmodules-install-check-C?
>>
>> Oooh, that is indeed an interesting observation. There are enough
>> examples now that it's hard to dismiss it as chance, but why would
>> the two runs be different?
>>
>>
>> It's not deterministic.
>>
>> I tested the theory that it was some other concurrent tests causing the issue, but that didn't wash. Here's what I did:
>>
>> for f in `seq 1 100`
>> do echo iteration = $f
>> meson test --suite xid_wraparound || break
>> done
>>
>> It took until iteration 6 to get an error. I don't think my Ubuntu instance is especially slow. e.g. "meson compile" normally takes a handful of seconds. Maybe concurrent tests make it more likely, but they can't be the only cause.
> Could you provide server logs in both OK and NG tests? I want to see
> if there's a difference in the rate at which tables are vacuumed.

See
<https://bitbucket.org/adunstan/rotfang-fdw/downloads/xid-wraparound-result.tar.bz2>

The failure logs are from a run where both tests 1 and 2 failed.

cheers

andrew

--
Andrew Dunstan
EDB:https://www.enterprisedb.com