>>>Manfred Koizar said: > effective_cache_size = 20000 (~ 160 MB) should be more adequate for a > 256 MB machine than the extremely conservative default of 1000. I > admit that the effect of this change is hard to benchmark. A way too > low (or too 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 ---------------------------(end of broadcast)--------------------------- TIP 6: Have you searched our list archives? http://archives.postgresql.org
