Thanks a lot, I'll try them all! Yes, I have a good external storage box with battery backed cache enabled. There are 64GB of RAM so I expected it'll help little bit to increase a buffer cache, but ok, will see if with 256MB it'll be better :-) What about "full_page_writes" ? seems it's "on" by default. Does it makes sense to put if off?.. Rgds, -Dimitri On 5/11/09, Kevin Grittner <Kevin.Grittner@xxxxxxxxxxxx> wrote: > Dimitri <dimitrik.fr@xxxxxxxxx> wrote: > >> PostgreSQL: 8.3.7 & 8.4 >> Server: Sun M5000 32cores >> OS: Solaris 10 > > Does that have a battery backed RAID controller? If so, is it > configured for write-back? These both help a lot with smoothing > checkpoint I/O gluts. > > We've minimized problems by making the background writer more > aggressive. 8.3 and later does a better job in general, but we've > still had to go with: > > bgwriter_lru_maxpages = 1000 > bgwriter_lru_multiplier = 4.0 > >> shared_buffers = 12000MB > > You might want to test with that set to something much lower, to see > what the checkpoint delays look like. We've found it best to use a > small (256MB) setting, and leave caching to the OS; in our > environment, it seems to do a better job of scheduling the disk I/O. > YMMV, of course. > > -Kevin > -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
