how do I size my buffer cache?
550825Sep 25 2007 — edited Sep 26 2007I know that the cache/hit ratio is flawed. I also have read a paper by Carrie Milsap that says that if your buffer cache is too big this can hurt performance. I am going to have 64 GBs(32 GB per RAC node) of RAM in production. Initially we will have about 500 GBs of data, but this may grow to 50 TBs.
All DML is direct path sql loader or insert append from external tables
All queries are oltp like. Users can fetch up to 150 rows, but most will get 1 row.
When we hit 50 GBs, we may have 15 RAC nodes with 32 GBs/RAM per node. This is probably more than we will need.
What indicators do I look for to size my Buffer cache? What about my PGA_AGGREGATE_TARGET?