Re: WAL segments (names) not in a sequence

On Sat, May 25, 2013 at 3:08 AM, German Becker <german.becker@gmail.com> wrote:
> Thanks Amit, I understand now. Is there a way to know/predict how many
> prealocated segments will there be in a certain moment? What does it deppend
> on?

Upthread, Fujii Masao-san suggested what might have happened that
caused these pre-allocated segments to be created. To quote him:

"WAL recycling is performed by checkpoint. Checkpoint always checks
whether there are WAL files no longer  required for crash recovery,
IOW, WAL files which were generated before the prior checkpoint
happened, and then if they are found, checkpoint tries to recycle
them."

Reading here would also help:
http://www.postgresql.org/docs/9.1/static/wal-configuration.html

If you are still using the same values as during this observation,
could you provide values for these postgresql.conf parameters:
checkpoint_segments, checkpoint_timeout, wal_keep_segments?


--
Amit Langote