On Mon, 21 Jan 2008, Hannes Dorbath wrote:
pgbench -i -s 10 -U pgsql -d bench && pgbench -t 1000 -c 100 -U pgsql -d bench
pgbench doesn't handle 100 clients at once very well on the same box as the server, unless you have a pretty serious system. The pgbench program itself has a single process model that doesn't handle the CFQ round-robin very well at all. On top of that, the database scale should be bigger than the number of clients or everybody just fights for the branches table. You said you tried with a larger scale as well, but that also vastly increases the size of the database which shifts to a completely different set of bottlenecks. See http://www.westnet.com/~gsmith/content/postgresql/pgbench-scaling.htm for more on this.
Try something more in the range of 4 clients/CPU and set the scale to closer to twice that (so with a dual-core system you might do 8 clients and a scale of 16). If you really want to simulate a large number of clients, do that on another system and connect to the server remotely.
-- * Greg Smith gsmith@xxxxxxxxxxxxx http://www.gregsmith.com Baltimore, MD ---------------------------(end of broadcast)--------------------------- TIP 2: Don't 'kill -9' the postmaster
