No experience.  I fact I'm learning from your experience.  While you say

"from my training at IBM that a cache hit rate of 99% and above is
recommended"

I found the following statement in the web interface.

The server database performs best with a cache hit ratio above 97% in the 
database bufferpool. To tune the bufferpool size, (a) reset the bufferpool 
statistics, (b) execute server operations that use the database, and (c) view 
the database details to see if the cache hit ratio is above 97%. If the cache 
hit ration is NOT above this percentage, increase the size of the BUFPOOLSIZE 
specification in the server options file.

Conflicting advice?  Perhaps your 97.7% is good and no problem exists.  Let's 
hear from others.  Please......


Ken
khoracek AT incsystem DOT com


>>> Sascha.Braeuning AT SPARKASSEN-INFORMATIK DOT DE 08/21/2002 12:46:04 AM >>>
Hi all,

first I've to thank all participants for the amount of answers I got on my
latest questions. Now I've got a new one which relates on the
bufferpoolsize and the cache hit rate on OS/390 TSM-Servers.

we use the following bufpoolsize:  32768
our chache hit rate:            97,7 %

I know from my training at IBM that a cache hit rate of 99 % and above is
recommended. Is it possible, that a lower cache hit rate can cause
performance-problems? What is your experience?


MfG
Sascha Bräuning


Sparkassen Informatik, Fellbach

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