SQL Server 2008 continues to hold on to memory

[9654]

So we have installed sql server 2008 on microsoft server 2008 web edition with 32GB memory.

the funny thing is that when i run jobs the memory keeps increasing and then it stops at 99% and stays there even though there are no jobs running on it.

shouldn't it normally come back to 10-15%.

my sysadmin says it is normal behavior of sql server 2008 where it caches info though i am not 100%convinced.

Any ideas.

 

[gmmastros]

Your sysadmin is right.

Hard drive access is many times slower than memory access. So... if you write a query, and that data is already in RAM, the query will run faster because the data does not need to be loaded from the drive.

The benefit here is improved performance.


-George

"The great things about standards is that there are so many to choose from." - Fortune Cookie Wisdom

 

[mrdenny]

Go back up George here...

SQL will cache data into memory and leave it there until such time that SQL needs to clear the space for other data. Basically the most recently looked at data is kept in the cache with the hope that you'll never need to go back to the disk for it.

If the memory is going up to 99% you'll want to limit the amount of memory that SQL Server has access to so that it doesn't eat up all the RAM on the server.

Denny
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