> 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"?
