-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Dmitry Potapov wrote: > Hello! > > We run a large (~66Gb) web-backend database on Postgresql 8.2.4 on > Linux. The hardware is Dual Xeon 5130 with 16Gb ram, LSI Megaraid U320-2x > scsi controller w/512Mb writeback cache and a BBU. Storage setup contains 3 > raid10 arrays (data, xlog, indexes, each on different array), 12 HDDs total. > Frontend application uses jdbc driver, connection pooling and threads. > > We've run into an issue of IO storms on checkpoints. Once in 20min > (which is checkpoint_interval) the database becomes unresponsive for about > 4-8 seconds. Query processing is suspended, server does nothing but writing What are your background writer settings? Joshua D. Drake - -- === The PostgreSQL Company: Command Prompt, Inc. === Sales/Support: +1.503.667.4564 24x7/Emergency: +1.800.492.2240 PostgreSQL solutions since 1997 http://www.commandprompt.com/ UNIQUE NOT NULL Donate to the PostgreSQL Project: http://www.postgresql.org/about/donate PostgreSQL Replication: http://www.commandprompt.com/products/ -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.6 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFGzF3nATb/zqfZUUQRAsV8AJ9Sg7yTUfTGKTB/vQdW5BucwgcRSgCeKqIE jzR7X5+n0x1Y91etGOBvvpE= =4Dc9 -----END PGP SIGNATURE----- ---------------------------(end of broadcast)--------------------------- TIP 3: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faq