> I'm guessing the high bursts are checkpoints. Can you check your log
> files for pg and see if you are getting warnings about checkpoint
> frequency? You can get some mileage here by increasing wal files.
Nope, nothing in the log. I have set:
wal_buffers=128
checkpoint_segments=128
checkpoint_timeout=3000
which I thought was rather generous. Perhaps I should set it even
higher for the loads?
> Have you determined that pg is not swapping? try upping maintenance_work_mem.
maintenance_work_mem = 524288 ... should I increase it even more?
Doesn't look like pg is swapping ...
> What exactly is your architecture? is your database server direct
> attached to the san? if so, 2gb/4gb fc? what san? have you bonnie++
> the san? basically, you can measure iowait to see if pg is waiting on
> your disks.
I'm currently running bonnie++ with the defaults ... should I change
the execution to better mimic Postgres' behavior?
RHEL 4.3 x86_64
HP DL585, 4 Dual Core Opteron 885s
16 GB RAM
2x300GB 10K SCSI320, RAID10
HP MSA1000 SAN direct connected via single 2GB Fibre Channel Arbitrated Loop
10x300GB 10K SCSI320, RAID10