Re: [HACKERS] More benchmarking of wal_buffers

Tom Lane wrote:
> "Christopher Kings-Lynne" <chriskl@familyhealth.com.au> writes:
> > I've just spent the last day and a half trying to benchmark our new database
> > installation to find a good value for wal_buffers.  The quick answer - there
> > isn't, just leave it on the default of 8.
>
> I don't think this is based on a useful test for wal_buffers.  The
> wal_buffers setting only has to be large enough for the maximum amount
> of WAL log data that your system emits between commits, because a commit
> (from anyone) is going to flush the WAL data to disk (for everyone).

What happens when the only transaction running emits more WAL log data
than wal_buffers can handle?  A flush happens when the WAL buffers
fill up (that's what I'd expect)?  Didn't find much in the
documentation about it...


--
Kevin Brown                          kevin@sysexperts.com