Re: tap tests on older branches fail if concurrency is used

On 1 June 2017 at 08:15, Andres Freund <andres(at)anarazel(dot)de> wrote:
> Hi,
>
> when using
> $ cat ~/.proverc
> -j9
>
> some tests fail for me in 9.4 and 9.5. E.g. src/bin/script's tests
> yields a lot of fun like:
> $ (cd ~/build/postgres/9.5-assert/vpath/src/bin/scripts/ && make check)
> ...
> # LOG: received immediate shutdown request
> # WARNING: terminating connection because of crash of another server process
> # DETAIL: The postmaster has commanded this server process to roll back the current transaction and exit, because another server process exited abnormally and possibly corrupted shared memory.
> # HINT: In a moment you should be able to reconnect to the database and repeat your command.
> ...
>
> it appears as if various tests are trampling over each other.

None of those scripts use PostgresNode, which I thought was added in
9.5, but apparently was actually introduced in 9.6. They do all their
own setup/teardown using TestLib.pm routines. TestLib uses a unique
tempdir for each test run, sets it as the unix socket directory, and
disables listening on tcp, so the most obvious conflict is hidden.

The immediate problem appears to be that they all use
tmp_check/postmaster.log . So anything that examines the logs gets
confused by seeing some other postgres instance's logs, or a mixture,
trampling everywhere.

I'll be surprised if there aren't other problems though. Rather than
trying to fix it all up, this seems like a good argument for
backporting the updated suite from 9.6 or pg10, with PostgresNode etc.
I already have a working tree with that done to use src/test/recovery
in 9.5, but haven't updated src/bin/scripts etc yet.

--
Craig Ringer http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Training & Services