Ron <rjpeace@xxxxxxxxxxxxx> writes: > One of the reasons for the wide variance in suggested values for pg > memory use is that pg 7.x and pg 8.x are =very= different beasts. > If you break the advice into pg 7.x and pg 8.x categories, you find > that there is far less variation in the suggestions. > Bottom line: pg 7.x could not take advantage of larger sums of memory > anywhere near as well as pg 8.x can. Actually I think it was 8.1 that really broke the barrier in terms of scalability of shared_buffers. Pre-8.1, the buffer manager just didn't scale well enough to make it useful to use more than a few hundred meg. (In fact, we never even bothered to fix the shared-memory-sizing calculations to be able to deal with >2GB shared memory until 8.1; if you try it in 8.0 it'll probably just crash.) regards, tom lane
