Question: A SQL Server has decreased in response time. Is there memory pressure on SQL Server? Is the server paging?

The server has 16383 megabytes of physical memory, but only 10 megabytes free memory are available. 

Answer: As more memory is consumed on a server , swapping to disk becomes a real possibility. Swapping to disk kills SQL Server  performance.Read more on SQL Server Performance Killers

How to troubleshoot Free Memory and SQL Server Performance

1) check the SQL Server is capped with a max memory.

2) check to see if free memory is at least over 500 MB. In my experience, when a server begins to drop below 500 MB , it is an indicator that it’s about to  start using the page file. Basically – operations that normally were running to memory , begin to read \ write to disk.

A quick way to check is to use Task manager |performance tab. It gives you a quick visual guide on the state of free memory.

Focus on what processes are utilising memory and act on them. Another option is to increase memory.

Read More on troubleshooting SQL Server memory pressure

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