> That's not entirely surprising. The problem with having lots of memory is... > that you have lots of memory. The operating system likes to cache, and this > includes writes. Normally this isn't a problem, but with 48GB of RAM, the > defaults (for CentOS 5.5 in particular) are to use up to 40% of that to cache > writes. I don't understand: don't you want postgresql to issue the fsync calls when it "makes sense" (and configure them), rather than having the OS decide when it's best to flush to disk? That is: don't you want all the memory to be used for caching, unless postgresql says otherwise (calling fsync), instead of "as soon as 1% of memory is used"? -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance