Also going through my head is '32 Kb bock's size (to match ffs and raid block's size)' - does that mean you have raid strip size = 32K? maybe try 128K (I know it sounds like a bad thing, but generally raid stripes of 128K->256K are better than 32K->64K)
regards
Mark
Pailloncy Jean-Gérard wrote:
Hello,
I found the same problem.
I use OpenBSD 3.3,
On Pentium 2,4 GHz with 1 Gb RAM, RAID 10.
With PostgreSQL 7.4.1 with 32 Kb bock's size (to match ffs and raid block's size)
With pg_autovacuum daemon from Pg 7.5.
I run a web indexer. sd0 raid-1 with system pg-log and indexer-log sd1 raid-10 with pg-data and indexer-data The sd1 disk achives between 10 and 40 Mb/s on normal operation.
When I get semwait in top, system waits ;-) Not much disk activity. Not much log in pg or indexer. Just wait....
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