On Tue, Apr 03, 2007 at 10:16:13PM +0800, John Summerfield wrote: > It is hitting the disk pretty hard now on this machine, but the laptop's > still going too, and the disk seems to run about half the time, part of > a second running, part idle (but the intervals are getting shorter). > > It struck me as fairly curious that neither postgresql nor the > application was hogging the CPU.
Why? Nothing about this seems likely CPU bound. It's probably I/O. I note is number: > IOwait: 2d 0:46:37.33 28.5% page dea: 16218135 which is pretty awful. Also > For each record, I update a non-key field in another table; the source > data for that other table is less than a megabyte. this is a real issue. Basically, you're constrained at the rotation speed of your disk, because for each record, you have to first find then update one row somewhere else. A -- Andrew Sullivan | [EMAIL PROTECTED] The plural of anecdote is not data. --Roger Brinner ---------------------------(end of broadcast)--------------------------- TIP 3: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faq