|
If you want a deeper understanding
of how the buffer cache is being utilized, there are a
few additional queries you can run to gain such
insight. If the keep and recycle buffer
caches are being used, you can run the
cacheobjcnt.sql query to get an idea on how many
objects have been assigned to each cache:
For the complete listing of the
cacheobjcnt.sql query, please refer to the online
Code Depot at
http://www.dba-oracle.com/bp/bp_book5_perf.htm.
This query looks at the sys.seg$
view and the output may resemble something like the
following:
CACHE OBJECTS
-----------------
default 2023
keep 5
Finally, you may wish to analyze
the buffer cache activity from time to time to see how
it is being utilized. The buffutl.sql script
will show you how full the cache currently is along
with the state of the buffers in the cache:
For the complete listing of the
buffutl.sql script, please refer to the online
Code Depot at
http://www.dba-oracle.com/bp/bp_book5_perf.htm.
This script queries the sys.x$bh, and sys.ts$
views and the output might look something like
this:
BUFFER_STATE
AMT_KB
------------------------
being read
5920
free
23568
read/mod
47952
read/notmod
0
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