I'd like to get the type of information in version 8 that I can get in version 9 through v$db_cache_advice in order to determine the size that the buffer cache should be. I've find sites that say you can set db_block_lru_extended_statistics to populate v$recent_bucket, but they say there is a performance hit. Can anyone tell me qualitatively how much of a performance hit this causes, and whether or not this is really the best/right way to do this?