On a Database server, Buffer pool is configured to utilize 80% of RAM and remaining 20% is for OS.
At the end of Normal load test on the application, database server shows available memory of around 50% on the server.
However, when application Peak load test is carried out, it starts with available memory of less than 10% on the DB server and then goes down till 7%. And no connections are made to SQL server during this time apart from the peak load test.
Is this acceptable behavior? Can we have available memory going down until 7% when memory allocated to OS is 20%?