64-bit topped out at 4 GB used

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64-bit topped out at 4 GB used

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Alan Spillert SSCommitted Points: 1964 More actions · Answer 1

After posting this question I changed the server memory.

min server memory (MB)1638416384

max server memory (MB)2048020480

awe enabled00

Version info:

Server has 24GB memory, 8 cores, 410GB disk in a RAID-5. Databases seem to be performing well.

Task Manager now shows Peak Mem Usage of 4,194,303;

Is AWE the problem? If I set Lock Pages in Memory is 4 GB enough for WinSrv03? or should I set memory lower?

Thank you all for your comments - much appreciated.

Gail Shaw SSC Guru Points: 1004504 More actions · Answer 2

Alan Spillert (8/13/2010)
After posting I changed the server memory max and min to 16384 and 20480 respectively

I hope you mean the other way around. Min should be lower than max.

The min isn't the minimum that SQL will allocate. It's the amount that, once allocated, SQL will never drop below. It's perfectly possible to have min memory set to a value and SQL never allocating that much.

Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability

We walk in the dark places no others will enter
We stand on the bridge and no one may pass

Paul White SSC Guru Points: 150467 More actions · Answer 3

Alan Spillert (8/13/2010)
Is AWE the problem? If I set Lock Pages in Memory is 4 GB enough for WinSrv03? or should I set memory lower?

You probably will want to set lock pages in memory at some stage - but that's not the reason why you're not seeing SQL Server use more memory. Is it just because it hasn't needed it yet? That seems favourite at the moment.

BTW, to get a good handle on all the technical stuff, please read this:

http://blogs.msdn.com/b/psssql/archive/2009/09/11/fun-with-locked-pages-awe-task-manager-and-the-working-set.aspx

Paul

Paul White
SQLPerformance.com
SQLkiwi blog
@SQL_Kiwi

Gail Shaw SSC Guru Points: 1004504 More actions · Answer 4

Alan Spillert (8/13/2010)
Task Manager now shows Peak Mem Usage of 4,194,303;

Rather than using task manager, can you use perfmon and check the Total Server memory counter? (under SQL Server:Memory Manager)

Is AWE the problem?

No. AWE is ignored and unnecessary on 64-bit

Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability

We walk in the dark places no others will enter
We stand on the bridge and no one may pass

Paul White SSC Guru Points: 150467 More actions · Answer 5

You can also use a DMV:

select [object_name],

counter_name,

cntr_value,

cntr_value / 1024.0 AS value_MB,

cntr_value / 1024.0 / 1024.0 AS value_GB

from sys.dm_os_performance_counters

where counter_name in

(

N'Total Server Memory (KB)',

N'Target Server Memory (KB)'

);

Paul White
SQLPerformance.com
SQLkiwi blog
@SQL_Kiwi

Alan Spillert SSCommitted Points: 1964 More actions · Answer 6

From the DMV:

object:

SQLServer:Memory Manager

counter_name: Target Server Memory (KB) cntr_value: 20971520

value_MB: 20480.000000

value_GB: 20.000000000000

SQLServer:Memory Manager

counter_name: Total Server Memory (KB)

cntr_value: 11700088

value_MB: 11425.867187

value_GB: 11.158073424804

The server has two 25GB databases, with moderate activity. What struck me originally was that memory in Task Manager has not moved from the 4,194,303. If SS05 had memory flexibility I would expect the number to fluctuate.

Gail Shaw SSC Guru Points: 1004504 More actions · Answer 7

I think this is another case where task manager is wrong (for whatever reason). Look at those perfmon counters. Total server memory (amount of memory currently used) is 11GB, not 4.

Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability

We walk in the dark places no others will enter
We stand on the bridge and no one may pass

Paul White SSC Guru Points: 150467 More actions · Answer 8

Well that shows that SQL Server is using just over 11GB, and is prepared to use up to 20GB.

Where exactly are you reading the Task Manager figure from, and what is the descriptive heading for the value?

Paul White
SQLPerformance.com
SQLkiwi blog
@SQL_Kiwi

Paul White SSC Guru Points: 150467 More actions · Answer 9

SSC answers appear to use RAID 1 :laugh:

Paul White
SQLPerformance.com
SQLkiwi blog
@SQL_Kiwi

Alan Spillert SSCommitted Points: 1964 More actions · Answer 10

I was looking at Windows Task Manager (Windows Server 2003) columns Mem Usage and Peak Mem Usage. Maybe they just don't show more then 4GB.

I will stick to using the DMVs in the future.

Thank you all.