On Tue, 4 Mar 2008, Ivan Voras wrote:
I'm curious about the math behind this - is ~4000 burst or sustained rate?
Average, which is not quite burst or sustained. No math behind it, just looking at a few samples of pgbench data on similar hardware. A system like this one is profiled at http://www.kaltenbrunner.cc/blog/index.php?/archives/21-8.3-vs.-8.2-a-simple-benchmark.html for example.
For common BBU cache sizes (256M, 512M), filling that amount with data is pretty trivial.
I don't have any good numbers handy but I think the burst is >6000, you only get that for a few seconds before all the caches fill and the rate drops considerably.
-- * Greg Smith gsmith@xxxxxxxxxxxxx http://www.gregsmith.com Baltimore, MD -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your Subscription: http://mail.postgresql.org/mj/mj_wwwusr?domain=postgresql.org&extra=pgsql-performance
