I have a persnickety problem with a particular table being aged out of the buffer cache. I have one query that runs on a defined basis. Sometimes when it is run, it does a lot of physical reads for this table. Other times, it does no physical reads.
So I decided to play around with a different buffer pool and let this table age out of cache on it's own terms rather than competing in the greater default pool. So far, it seems to be working pretty well.
I'll admit it, it's been a long time since I used a KEEP pool. Some helpful KEEP pool resources:
Edward Stoever at Database-expert.com
Standard Disclaimer: I understand that 99.9% of the time you don't need a KEEP pool. In this situation it seems to be warranted.