On Wed, 2005-07-13 at 17:57 -0400, Tom Lane wrote:
> I'm not certain how important that really is; it was part of
> Vadim's original design for WAL and no one ever particularly
> questioned it.
Anybody setting checkpoint_segments high is likely to have a dedicated
WAL disk anyway, which easily gives you space for 1000s of WAL segment
files, given current disk sizes. So saving space shouldn't be a reason
to want to remove that.
It seems practical sense to have more than one checkpoint available. The
whole purpose of WAL is robustness and recoverability. All DBAs (should)
keep both their last backup and the one before that (at least), with
many sites specifying an automatic retention history of 7 or more. That
same philosophy should work with the WAL files also.
So, overall, I see no reason to change that feature.
Best Regards, Simon Riggs
