Hi, I am trying to optimize my Debian Sarge AMD64 PostgreSQL 8.0 installation, based on the recommendations from "the Annotated POSTGRESQL.CONF Guide for PostgreSQL" (http://www.powerpostgresql.com/Downloads/annotated_conf_80.html). To see the result of the recommendations I use pgbench from postgresql-contrib. I have 3 questions about pgbench: 1. Is there a repository somewhere that shows results, using and documenting different kinds of hard- and software setups so that I can compare my results with someone elses? 2. Is there a reason for the difference in values from run-to-run of pgbench: The command I used (nothing else is done on the machine, not even mouse movement): jkr@Panoramix:/usr/lib/postgresql/8.0/bin$ ./pgbench -c 10 -t 1000 test Results for 4 consecutive runs: tps = 272.932982 (including connections establishing) tps = 273.262622 (excluding connections establishing) tps = 199.501426 (including connections establishing) tps = 199.674937 (excluding connections establishing) tps = 400.462117 (including connections establishing) tps = 401.218291 (excluding connections establishing) tps = 223.695331 (including connections establishing) tps = 223.919031 (excluding connections establishing) 3. It appears that running more transactions with the same amount of clients leads to a drop in the transactions per second. I do not understand why this is (a drop from more clients I do understand). Is this because of the way pgbench works, the way PostgrSQL works or even Linux? jkr@Panoramix:/usr/lib/postgresql/8.0/bin$ ./pgbench -c 10 -t 10 test tps = 379.218809 (including connections establishing) tps = 461.968448 (excluding connections establishing) jkr@Panoramix:/usr/lib/postgresql/8.0/bin$ ./pgbench -c 10 -t 100 test tps = 533.878031 (including connections establishing) tps = 546.571141 (excluding connections establishing) jkr@Panoramix:/usr/lib/postgresql/8.0/bin$ ./pgbench -c 10 -t 1000 test tps = 204.344440 (including connections establishing) tps = 204.533627 (excluding connections establishing) jkr@Panoramix:/usr/lib/postgresql/8.0/bin$ ./pgbench -c 10 -t 10000 test tps = 121.486803 (including connections establishing) tps = 121.493681 (excluding connections establishing) TIA -- Groeten, Joost Kraaijeveld Askesis B.V. Molukkenstraat 14 6524NB Nijmegen tel: 024-3888063 / 06-51855277 fax: 024-3608416 e-mail: J.Kraaijeveld@xxxxxxxxxx web: www.askesis.nl
