leo xu wrote: > I test postgresql database performance recently,i set > log_min_duration_statement=1000; > i monitor pg_log file,i find too many execue S_2:commit > 10.0.44.21:30170:2012-04-28 11:38:46.340 CSTLOG: duration: 1050.679 ms > execute S_2: COMMIT > > 10.0.44.21:30208:2012-04-28 11:38:46.340 CSTLOG: duration: 1050.576 ms > execute S_2: COMMIT > > 10.0.44.21:30318:2012-04-28 11:38:46.340 CSTLOG: duration: 1028.171 ms > execute S_2: COMMIT > > ........ > > please explain what meaning,how to cause it ,how to deal with it?thank you ! It would be helpful to know *how* you test performance. Also, the PostgreSQL version, operating system, software and hardware configuration might be interesting. If COMMIT takes a long time, my first guess would be that it takes a long time to write the transaction log (the WAL files in pg_xlog) to disk. You can try to verify that with a disk performance measuring tool for your operating system. Yours, Laurenz Albe -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general