You can use on NON-PRODUCTION servers, the V$RECENT_BUCKET view. To enable it, setup DB_BLOCK_LRU_EXTENDED_STATISTICS to nonzero value in init.ora file and enable collection of V$RECENT_BUCKET statistics from V$SYSSTAT.

Detailed procedure could be found Here

Hope that helps,

clio_usa
OCP DBA 8/8i/9i
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