Re: PATCH: Split stats file per database WAS: autovacuum stress-testing our system

Alvaro Herrera escribió:
> Here's a ninth version of this patch. (version 8 went unpublished). I
> have simplified a lot of things and improved some comments; I think I
> understand much of it now. I think this patch is fairly close to
> committable, but one issue remains, which is this bit in
> pgstat_write_statsfiles():
>
> /* In any case, we can just throw away all the db requests, but we need to
> * write dummy files for databases without a stat entry (it would cause
> * issues in pgstat_read_db_statsfile_timestamp and pgstat wait timeouts).
> * This may happen e.g. for shared DB (oid = 0) right after initdb.
> */

I think the real way to handle this is to fix backend_read_statsfile().
It's using the old logic of considering existance of the file, but of
course now the file might not exist at all and that doesn't mean we need
to continue kicking the collector to write it. We need a mechanism to
figure that the collector is just not going to write the file no matter
how hard we kick it ...

--
Álvaro Herrera http://www.2ndQuadrant.com/
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