Re: prevent immature WAL streaming - Mailing list pgsql-hackers

From Alvaro Herrera
Subject Re: prevent immature WAL streaming
Date
Msg-id 202111101209.sjr4tfcrjr34@alvherre.pgsql
Whole thread Raw
In response to Re: prevent immature WAL streaming  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: prevent immature WAL streaming
List pgsql-hackers
On 2021-Nov-09, Tom Lane wrote:

> This is still happening off and on, which makes it look like a
> timing-sensitive problem.  Confirming that, I can make it fail
> every time by adding a long sleep just ahead of where
> 026_overwrite_contrecord.pl captures $initfile.  On reflection
> I think the problem is obvious: if autovacuum does anything
> concurrently with the test's startup portion, it will cause the
> carefully-established WAL insertion point to move into the
> next segment.  I propose to add "autovacuum = off" to the
> test's postmaster configuration.

Ooh, of course.

> Also, I think we want
> 
> -ok($initfile != $endfile, "$initfile differs from $endfile");
> +ok($initfile ne $endfile, "$initfile differs from $endfile");
> 
> The existing coding works as long as all characters of these
> WAL segment names happen to be decimal digits, but ...

Argh!

Thanks for taking care of these issues.

-- 
Álvaro Herrera         PostgreSQL Developer  —  https://www.EnterpriseDB.com/
"La conclusión que podemos sacar de esos estudios es que
no podemos sacar ninguna conclusión de ellos" (Tanenbaum)



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