Click here to monitor SSC
SQLServerCentral is supported by Red Gate Software Ltd.
 
Log in  ::  Register  ::  Not logged in
 
 
 
        
Home       Members    Calendar    Who's On


Add to briefcase

Analysis Services Not Taking Allocated Memory Expand / Collapse
Author
Message
Posted Friday, March 14, 2014 12:34 PM
Forum Newbie

Forum NewbieForum NewbieForum NewbieForum NewbieForum NewbieForum NewbieForum NewbieForum Newbie

Group: General Forum Members
Last Login: Thursday, October 9, 2014 4:52 PM
Points: 7, Visits: 214
We have run into an issue on a dedicated SSAS 2012 SP1 server where the allocated memory is not being utilized, causing some slowness in use, connections, and queries.

Total Memory on the server is 512, and after startup, the utilized memory gets up to a max of 60GB and stops there. Checking the Resource Monitor, msmdsrv.exe is only taking around 39GB overall. With the current properties, that should be at 330GB. Am I missing something in the settings or in configuration that should be changed?


Version: SQL Server 2012 SP1 Enterprise (11.0.3000)
OS: Windows Server 2012 Datacenter - Fully patched and up to date
Databases: 2 Tabular models
Server: 512GB RAM

Current memory configuration:
Hard Memory Limit - 0 (Default)
LowMemoryLimit - 65% (Default)
TotalMemoryLimit - 95% (Default is 80)
VertiPaqMemoryLimit - 60% (Default)
VertiPaqPaginingPolicy - 1 (Default)
MemoryHeapType - 2 (Default)


Thank you!
Post #1551290
Posted Friday, March 14, 2014 1:51 PM
Valued Member

Valued MemberValued MemberValued MemberValued MemberValued MemberValued MemberValued MemberValued Member

Group: General Forum Members
Last Login: Yesterday @ 9:44 AM
Points: 67, Visits: 708
Are you sure the SSAS needs the memory?
SSAS does not grab and hold memory like SQL Server, it only takes the memory that is necessary to keep the model in memory.
The LowMemoryLimit is not the minimum amount of memory taken ( 512 * 65% ~ 330), but the Specifies the threshold amount of memory allocated by Analysis Services at which it will begin cleaning caches to lower memory usage.
You can find more details here: http://msdn.microsoft.com/en-us/library/dn393915.aspx
Post #1551341
Posted Saturday, March 15, 2014 3:52 PM
Forum Newbie

Forum NewbieForum NewbieForum NewbieForum NewbieForum NewbieForum NewbieForum NewbieForum Newbie

Group: General Forum Members
Last Login: Thursday, October 9, 2014 4:52 PM
Points: 7, Visits: 214
Thanks for pointing me in the right direction. That whitepaper has helped quite a bit. It does look like the tabular models, currently, are only about 50GB in size total.

After further investigation it looks like the Excel workbooks that are querying the models are hitting a tipping point of performance after selecting 6-7 slicers, at which point the data refresh takes 2-3 minutes. We will continue to look into this.

Thank you!
Post #1551523
« Prev Topic | Next Topic »

Add to briefcase

Permissions Expand / Collapse