On Wed, Oct 06, 2004 at 10:01:42AM -0700, Mark Wong wrote: > On Mon, Oct 04, 2004 at 02:42:43PM -0400, Greg Stark wrote: > > Mark Wong <[EMAIL PROTECTED]> writes: > > > > > Links to results are here: > > > 7.5devel - http://www.osdl.org/projects/dbt2dev/results/dev4-010/128/ > > > 8.0beta3 - http://www.osdl.org/projects/dbt2dev/results/dev4-010/180/ > > > > Are those cyclic spikes an artifact of the load of the tests? Or are they > > artifacts of the postgres checkpoint process? > > In the past, they have been artifacts of the checkpoint process. They > do smooth out as I increase the checkpoint segments and the timeout. > Although I know that doesn't exactly exclude other explanations.
Another knob to test would be bgwriter parameters, say bgwriter_percent to maybe 5 or 10. That should distribute more evenly the load. http://archives.postgresql.org/pgsql-hackers/2004-09/msg00623.php -- Alvaro Herrera (<alvherre[a]dcc.uchile.cl>) "La rebeldía es la virtud original del hombre" (Arthur Schopenhauer) ---------------------------(end of broadcast)--------------------------- TIP 7: don't forget to increase your free space map settings
