Re: [PERFORM] Query plan looks OK, but slow I/O - settings advice?

2005-08-19 Thread Jeffrey W. Baker
On Tue, 2005-08-16 at 10:46 -0700, Roger Hand wrote: The disks are ext3 with journalling type of ordered, but this was later changed to writeback with no apparent change in speed. They're on a Dell poweredge 6650 with LSI raid card, setup as follows: 4 disks raid 10 for indexes (145GB) -

Re: [PERFORM] Query plan looks OK, but slow I/O - settings advice?

2005-08-19 Thread Gavin Sherry
The query plan does *not* look okay. electric=# EXPLAIN ANALYZE electric-# SELECT datavalue, logfielddatatype, timestamp FROM logdata_recent electric-# WHERE (logfielddatatype = 70 OR logfielddatatype = 71 OR logfielddatatype = 69) electric-# AND graphtargetlog = 1327 electric-# AND

Re: [PERFORM] Query plan looks OK, but slow I/O - settings advice?

2005-08-19 Thread Roger Hand
Jeffrey W. Baker wrote: On Tue, 2005-08-16 at 10:46 -0700, Roger Hand wrote: The disks are ext3 with journalling type of ordered, but this was later changed to writeback with no apparent change in speed. They're on a Dell poweredge 6650 with LSI raid card, setup as follows: 4 disks raid 10

[PERFORM] Query plan looks OK, but slow I/O - settings advice?

2005-08-18 Thread Roger Hand
Summary === We are writing to the db pretty much 24 hours a day. Recently the amount of data we write has increased, and the query speed, formerly okay, has taken a dive. The query is using the indexes as expected, so I don't _think_ I have a query tuning issue, just an io problem. The