Cry about...
Oracle How To ...

Tuning the cache hit ratio

The cache miss ratio is the the number of cache misses compared to the total number of cache read attempts. This is calculated as follows:

Select sum(getmisses) / sum(gets) "Miss ratio"
From v$rowcache;

The miss ratio should be less than 15%. If this is not the case, increase the initialisation parameter SHARED_POOL_SIZE.

These notes have been tested against Oracle 7.3.4, Oracle 8.0.5, Oracle 8.1.5 and Oracle 9.0.1 and may apply to other versions as well.

This page represents one page of many pages of notes I made whilst working with Oracle 7 through to 10i. I now no longer work with Oracle databases, but hope that these notes will continue to be of benefit to others.

About the author: is a dedicated software developer and webmaster. For his day job he develops websites and desktop applications as well as providing IT services. He moonlights as a technical author and consultant.