SQL Server Performance Forum – Threads Archive
AWE Enabled
Hi all, Can anybody tell me , that how can we check , whether our sql server ‘AWE’ option is enabled (or) not. Actually ,i m new to sql server. so, i need help,plz. System Configuratin: OS — Win 2003 Standard sp1 Sql server 2005 sp1 ( I have only one instance ) System configuration = 3.83 GB of RAM ——– When i right click the sql server instance , select Properties and then on the ‘General’ tab , i see ‘Memory’ assigned to that instance as = 3927 (MB). Does this mean that, someone already has enabled AWE option. That’s the reason its showing memory = 3927 MB. (or) i have to enable it externally. Thanks.Use the command: sp_configure ‘awe enabled’ to see if AWE is enabled.
Also you can take help of SYSMON (PERFMON) in this case for the usage of resources. Satya SKJ
Microsoft SQL Server MVP
Writer, Contributing Editor & Moderator
http://www.SQL-Server-Performance.Com
This posting is provided AS IS with no rights for the sake of knowledge sharing. Knowledge is of two kinds. We know a subject ourselves or we know where we can find information on it.
Thanks sir for replying. When i run the command, use master
go
sp_configure ‘awe enabled’,1
go
reconfigure
go The output i got is:
name min max config_value run_value
awe enabled010 0 So, the vaulu of config_value = 0 means it is not enabled. Then can you plz tell , what could be the reason that its showing memory = 3927 MB. Thanks.
After executing this dbcc command, DBCC Memorystatus This is the output i got and many more boxes came following this one: VM Reserved 1659980
VM Committed 1659100
AWE Allocated 0
Reserved Memory 1024
Reserved Memory In Use 0 So , this mean that, 1.5GB reserved and 1.5GB committed and AWE = 0
means , it is not enabled. But, when we right click the sql server instance, and then click
properties and then on the ‘General Tab’, when we look for memory, it
shows memory = 3927 MB. Is this showing the total memory of the server, doesnt considering
AWE enabled (or) not ? Thanks.
Can anybody reply to this plz.
N SQL; Are you seeing an excessive amount of paging? Or poor performance from the SQL DB?
CG2000 Actually,yesterday one of my report yesterday failed with the error ( An error occured during local report processing and exception system.outotmemoryException). Then, i ran today, i went. I dont know , what cause the problem. So, because of this i started looking at awe option. But, can u tell me , if possible, the memory which i am seeing in sql server instance, what does it mean. Does it showing, the total server memory , even though awe is not enabled, as u can see from prevoious post. Thanks.
Yes, SQL is utilising all the available memory and as per CG’s information if you are not getting any performance issues then you need not worry.
That exception error may be related with other activities on the server, so check what kind of processes and jobs are running at that time. Satya SKJ
Microsoft SQL Server MVP
Writer, Contributing Editor & Moderator
http://www.SQL-Server-Performance.Com
This posting is provided AS IS with no rights for the sake of knowledge sharing. Knowledge is of two kinds. We know a subject ourselves or we know where we can find information on it.
Hi Satya, When we carefully examine the results from "DBCC MEMORYSTATUS", the output i am getting is : VM Reserved——– 1660492
VM Committed—– 1659612
AWE Allocated——— 0
Reserved Memory—— 1024
Reserved Memory In Use—- 0 As we can see "AWE Allocated =0" , so how sql server can able to utilize full server memory. Any Suggestions. Thanks.
SQL 2005 BOL says: "If the available physical memory is less than the user mode virtual address space, AWE cannot be activated. In this case, SQL Server runs in non-AWE mode, regardless of the setting of the awe enabled option." So you might have to adjust the amount of page space (Virtual Address Space) MS Server 2003 is allocating (if I am reading this right). 4GB isn’t a whopping amount of RAM, versus the amount of available HDD storage space in most current servers. You might want to adjust and see what performance difference you see. I think I would put an additional load on the server without AWE enabled and run perfmon (setup some counters) with you current settings – see what happens in terms of paging and buffering with the higher load.
I thought you have got those figures from Task manager, anyway bear in mind if you enable the AWE then you will not be able to get back unless you restart SQL services. This is necessary if you are using the server for any other applications other than SQL in this case. To avoid hurting the performance of other applications, configure max server memory to leave some additional memory free to allow for the varying needs of other applications and the operating system. Also I recommend by setting a value for max server memory each time you enable AWE.
BOL confirms:
SQL Server 2005 supports dynamic allocation of AWE memory on Windows Server 2003. During startup, SQL Server reserves only a small portion of AWE-mapped memory. As additional AWE-mapped memory is required, the operating system dynamically allocates it to SQL Server.
The physical memory accessible by AWE depends on which operating system you are using. The following list provides the maximum physical memory accessible by each Windows Server 2003 operating system at the time of writing. Windows Server 2003, Standard Edition supports physical memory up to 4 GB. Windows Server 2003, Enterprise Edition supports physical memory up to 32 GB. Windows Server 2003, Datacenter Edition supports physical memory up to 64 GB. Satya SKJ
Microsoft SQL Server MVP
Writer, Contributing Editor & Moderator
http://www.SQL-Server-Performance.Com
This posting is provided AS IS with no rights for the sake of knowledge sharing. Knowledge is of two kinds. We know a subject ourselves or we know where we can find information on it.
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