Available Memory MB & % Memory Free - not static

SQL uses all the memory given to it, and wont release it easily.... yet.. a snapshot taken at a specific time each day gives a different value for
Available Memory MB      
% Memory Free

the max memory to use for SQL is set to default.
min 0; max 2147483647 MB.
Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

PadawanDBAOperational DBACommented:
Is the value greater than or less than the previous snapshot?  SQL Server will release memory easily enough, by the way.  It requires a low memory event to be fired by windows Resource Manager and SQL Server's buffer pool will recalculate its target commit (how much memory it is allowed to have).  Also, it's important to note that SQL server doesn't just automatically gobble up all the memory on the server, it will request memory space as necessary by the data load in the instance.  As that demand grows, it will gain a larger footprint for, most notably, the data page cache.  When the target commit is reached, it's not going to grow any more (max memory is a way to conrol over the target commit value - it can't be lower than min memory nor higher than max memory) and will begin aging out old pages using an LRU-2 algorithm (essentially maintains some semblance of a historical view of when the data pages were last accessed) in order to determine the most optimal pages to flush from cache to allow new pages to be read into memory - it uses a lazywriter thread to perform this work, one by default, but in high demand cases other processes will spool up lazywriter helper threads until the memory pressure is resolved.


As a more practical aside: the low memory event usually means the memory is *really* low - you should configure your max and min memory settings.

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
lcohanDatabase AnalystCommented:
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
Microsoft SQL Server 2008

From novice to tech pro — start learning today.