Brad Nicholson wrote:
Joshua D. Drake wrote:
Brad Nicholson wrote:
I'm investigating a potential IO issue. We're running 7.4 on AIX
5.1. During periods of high activity (reads, writes, and vacuums),
we are seeing iostat reporting 100% disk usage. I have a feeling
that the iostat numbers are misleading. I can make iostat usage
jump from less than 10% to greater than 95% by running a single
vacuum against a moderate sized table (no noticeable change in the
other activity).
Well that isn't surprising. Vacuum is brutal especially on 7.4 as
that is pre background writer. What type of IO do you have available
(RAID, SCSI?)
Data LUN is RAID 10, wal LUN is RAID 1.
How many disks?
