There is a script on the Ixora web site (whence_invalidations.sql) that can help
you to find out what has caused the invalidations. However, there is no
relationship between library cache invalidations and buffer cache performance,
so I suggest that you look elsewhere for the cause of the change in your cache
hit ratio. It may just be the way you are calculating the hit ratio. There are a
few gotchas that are explained in the Ixora web tip on the topic. Otherwise, you
may have lost some indexes, or something like that.


-----Original Message-----
Sent: Wednesday, 6 September 2000 3:02


Sometime last week our db buffer cache hit ratio went from 96% to 40% where
it has remained since.  The only clue on the trail to track it down is the
high number of invalids in the sql area when I look at the hitratio.

How can I find out what is causing the invalid sql?