Re: checkpoint_timeout irrelevant in 8.1.9

George Wilk wrote:
> According to the WAL config documentation correctly, checkpoints are created
> every
> <mk:@MSITStore:C:\Program%20Files\PostgreSQL\8.2\pgAdmin%20III\docs\en_US\pg
> admin3.chm::/pg/runtime-config-wal.html#guc-checkpoint-segments>
> checkpoint_segments log segments, or every
> <mk:@MSITStore:C:\Program%20Files\PostgreSQL\8.2\pgAdmin%20III\docs\en_US\pg
> admin3.chm::/pg/runtime-config-wal.html#guc-checkpoint-timeout>
> checkpoint_timeout seconds, whichever comes first.  However, it seems as
> though setting my checkpoint_timeout has no effect on checkpoint creation (
> I have it set to 30 seconds).  Forcing checkpoint by running psql -c
> CHECKPOINT mydb doesn't do the trick either.  Checkpoints are created solely
> based on the checkpoint_segments logs reaching their configured size.

You are misunderstand what a checkpoint is.  Also, why would you need a
checkpoint every 30 seconds escapes me.  What you probably want is to
archive the WAL segment currently in use.  There's a function you can
use for that, pg_switch_xlog().

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