[new] DB Cache Hit Rate Question
2003-02-19 22:07:45
Hi Guys!
In following this thread, I thought I'd check out customer experience
with a stock TSM server they have.
q db f=d showed the DB hit rate at 85%
q opt showed the bufpoolsize at 2350
This was with auto tuning.
After disabling auto-bufpool tuning, I increased the
bufpoolsize to 131072 (on a 2G system also running one
other application) and notices the hit rate climb to
99.2% over the next two days.
VMstat shows 'avm' of around 260000 pages, or just over
a GIG. I therefore _assume_ the remainder constitutes buffer-cache.
vmstat showed absolutely no paging for the period I monitored
(about 6 hours during a working day), so would it be safe to
further increase the bufpoolsize?
Also, the customer noticed a TSM db backup which took 35 minutes
two days ago, now completes in 12 minutes.
Could that indicate a problem?
TIA
Dave
|
|
|