Estimating cache size

I want to know how to estimate the size of tha cache memory, that is the value of the parameter:
DB_CACHE_SIZE
is there any criteria to estimate it??
I'm working with partiotioned tables of ten millions rows. This tables are indexed and a normal query on this tables return about 10000 rows.
The maximun number of users working simultaneous and making sql's to this tables are 60.
Any advice about cache size will be greatly apreciatted.
Thanks in advance

Hi,
if you have the parameter db_cache_advice set to ON then the view v$db_cache_Advice can show you the expected I/O for an estmated cache size.
You query this view under typical workload, not directely after startup. With this you can find out if it would meake sense to increase the buffer cache.
Hope this helps,
regards,
Lutz

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