Oracle DB Memory Allocation Sizing
Hi,
I have to create an standalone Oracle DB instance and the spec of the environment is given below.
1. OS - Windows 2003 R2 server - 64 Bit
2. RAM - 64GB RAM
3. Oracle 11g R2 Ent Edt - 64 Bit (Dedicated Server Mode)
4. No other applications runs in this server other than stand alone database.
What is the recommended SGA and PGA allocation for this environment?
Some docs say the below :
"If you only have Oracle on the server, start by reserving 10% of RAM for Linux or 20% or RAM for Windows. With whatever RAM is left-over:
SGA Sizing - Optimize the instance by determining the optimal size for db_cache_size, shared_pool_size, etc.
PGA Sizing - Determine the optimal total RAM for PGA regions (pga_aggregate_target) to minimize disk sorts and maximize hash joins"
During DBCA DB creation part the recommended memory_target (SGA+PGA) size given by Oracle is 40% of total RAM.If i allocate 20% for windows OS and 40% for memory_target (SGA+PGA) i am wasting the remaining 40% of RAM.
In my case i have 64GB RAM. So I can discard 12.8 GB for windows OS.
Can i allocate remaining 80% for SGA and PGA ? If No why ?
If yes how much % of available free RAM i have to allocate each for sga_target and pga_aggregate_target?
Thanks,
Ashok Kumar.G