>>>Manfred Koizar said:> effective_cache_size = 20000 (~ 160 MB) should be more adequate for a> 256 MB machine than the
extremelyconservative default of 1000. I> admit that the effect of this change is hard to benchmark. A way too> low
(ortoo high) setting may lead the planner to wrong conclusions.
The default on BSD systems is 10% of the total RAM, so on a 256MB machine this
would be ~26MB or effective_cache_size = 32000.
One could always modify the kernel to support much larger value, but I doubt
this is done in many cases and the usefulness of larger buffer cache is not
obvious in the presence of many fsync calls (which might be typicall). I could
be wrong, of course :)
In any case, the default is indeed low and would prevent using indexes on
larger tables, where they are most useful.
Daniel
