Well, no.. I don't know that. But in a worst case scenario, where everything is using max, there won't be 3.5 GB for the OS. But for the OS + Postgre (combined) there will be 2.5 + 2.75 .. But it seems that there is no greater danger in the effective cache, but a good setting would be nice :) Is the effective cache only the one for the OS ? not for them combined ?
Sincerely / Jen On Wed, Apr 8, 2009 at 7:44 PM, David Wilson <david.t.wil...@gmail.com>wrote: > On Wed, Apr 8, 2009 at 12:24 PM, Jennifer Trey <jennifer.t...@gmail.com> > wrote: > > > I think I might have misunderstood the effective cache size. Its measured > in > > 8kB blocks. So the old number 449697 equals 3.5 GB, which is quite much. > > Should I lower this? I had plans to use 2.75GB max. Can I put 2.75GB > there? > > Should I leave it? > > The effective cache size setting is merely letting postgres know how > much caching it can expect the OS to be doing. If you know that the OS > isn't going to have more than 2.75 GB available for caching DB files, > then by all means reduce it. The setting by itself doesn't affect > postgres memory usage at all, though. > > -- > - David T. Wilson > david.t.wil...@gmail.com >
