Re: archive_timeout, checkpoint_timeout

I was referring to this post:
http://archives.postgresql.org/pgsql-hackers/2007-10/msg01361.php

The test database was completely idle. WAL files were only being
archived at the interval specified in checkpoint_timeout (I was using
the default value) -- archive_timeout didn't make them happen any faster.

Upon retesting, archive_timeout is working properly when there are
regular updates happening to the database.

Thanks for your help!
--Rob Adams

Tom Lane wrote:
> Rob Adams <robfadams(at)cox(dot)net> writes:
>> archive_timeout only seems to work if it's >= checkpoint_timeout.
>
> Hmm, no, they should be pretty independent. Define "seems to work"
> please?
>
> One possible connection is that an xlog file switch will not actually
> happen unless some xlog output has been generated since the last switch.
> If you were watching an otherwise-idle system then maybe the checkpoint
> records are needed to make it look like a switch is needed. OTOH if
> it's *that* idle then the checkpoints should be no-ops too. So we
> need a bit more context to understand what's happening. How often
> do real updates happen on your database?
>
> regards, tom lane
>