Scott Marlowe wrote:
effective_cache_size is pretty easy to set, and it's not real
sensitive to small changes, so guesstimation is fine where it's
concerned. Basically, let your machine run for a while, then add the
cache and buffer your unix kernel has altogether (top and free will
tell you these things). If you're running other apps on the server,
make a SWAG (scientific wild assed guess) how much the other apps are
pounding on the kernel cache / buffer and set effective_cache_size to
how much you think postgresql is using of the total and set it to
that.
FWIW - The buffered|cached may well be called something different if you
are not on Linux (I didn't see any platform mentioned - sorry if I
missed it) - e.g for Freebsd it is "Inactive" that shows what the os is
caching and "Cached" actually means something slightly different... (yep
that's caused a lot of confusion in the past...)
Cheers
Mark
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