Comments for Ajmer Dhariwal's SQL Server blog http://www.eraofdata.com/blog SQL Server posts that DBAs will (hopefully) find useful. Mon, 23 Jan 2012 21:18:03 +0000 hourly 1 http://wordpress.org/?v=3.2.1 Comment on SQL Server memory configuration by Ajmer Dhariwal http://www.eraofdata.com/blog/sql-server-memory-configuration/#comment-5076 Ajmer Dhariwal Mon, 23 Jan 2012 21:18:03 +0000 http://www.eraofdata.com/blog/?p=3#comment-5076 Good question. Although SSIS and SSAS from part of the SQL Server stack they have completely different memory architectures so you would have to monitor their peak memory usage by reducing SQL Server's max memory settings to ensure SSIS and SSAS have enough room and to see how high their memory usage goes under peak loading. In my experience on servers where we had to run SSAS/SSIS alongside SQL Server (something we tried to avoid if they were high load systems) the SSIS/SSAS process will peak at a certain level depending on the workload thrown at them and we would adjust SQL Server's memory settings accordingly, or just add additional memory if the peak uses of the SSIS/SSAS processes took up too many resources. I'd also highly recommend adjusting SQL Server's max degree of parallelism settings otherwise SQL Server will saturate the CPUs denying SSIS/SSAS cpu time when any e.g. data loading/transformation is taking place. You can also look at SQL Server's CPU affinity settings (bearing in mind SSIS/SSAS don't yet have similar functionality). Good question. Although SSIS and SSAS from part of the SQL Server stack they have completely different memory architectures so you would have to monitor their peak memory usage by reducing SQL Server’s max memory settings to ensure SSIS and SSAS have enough room and to see how high their memory usage goes under peak loading.
In my experience on servers where we had to run SSAS/SSIS alongside SQL Server (something we tried to avoid if they were high load systems) the SSIS/SSAS process will peak at a certain level depending on the workload thrown at them and we would adjust SQL Server’s memory settings accordingly, or just add additional memory if the peak uses of the SSIS/SSAS processes took up too many resources. I’d also highly recommend adjusting SQL Server’s max degree of parallelism settings otherwise SQL Server will saturate the CPUs denying SSIS/SSAS cpu time when any e.g. data loading/transformation is taking place. You can also look at SQL Server’s CPU affinity settings (bearing in mind SSIS/SSAS don’t yet have similar functionality).

]]> Comment on SQL Server memory configuration by rick http://www.eraofdata.com/blog/sql-server-memory-configuration/#comment-5074 rick Mon, 23 Jan 2012 17:10:40 +0000 http://www.eraofdata.com/blog/?p=3#comment-5074 Hello, very good post, thank you. Question: how do you consider and factor in memory needs of SQL services such as SSIS, SSAS etc? These applications utilize memory outside of the SQL mem manger's control, yes? thank you for insight into this question. Rick Hello, very good post, thank you.
Question: how do you consider and factor in memory needs of SQL services such as SSIS, SSAS etc? These applications utilize memory outside of the SQL mem manger’s control, yes?

thank you for insight into this question.
Rick

]]> Comment on SQL Server memory configuration by Ajmer Dhariwal http://www.eraofdata.com/blog/sql-server-memory-configuration/#comment-4798 Ajmer Dhariwal Fri, 13 Jan 2012 13:25:32 +0000 http://www.eraofdata.com/blog/?p=3#comment-4798 Yup, you're hitting that infamous bug. Apply the last CU for <a href="http://support.microsoft.com/kb/904660" rel="nofollow">SP4</a> (build 2187). Yup, you’re hitting that infamous bug. Apply the last CU for SP4 (build 2187).

]]> Comment on SQL Server memory configuration by Adam http://www.eraofdata.com/blog/sql-server-memory-configuration/#comment-4776 Adam Fri, 13 Jan 2012 02:26:17 +0000 http://www.eraofdata.com/blog/?p=3#comment-4776 Is it because of the bug you mentioned in your post or is there any memory cap for sql 2000 on windows 2003? Is it because of the bug you mentioned in your post or is there any memory cap for sql 2000 on windows 2003?

]]> Comment on SQL Server memory configuration by Adam http://www.eraofdata.com/blog/sql-server-memory-configuration/#comment-4775 Adam Fri, 13 Jan 2012 02:23:34 +0000 http://www.eraofdata.com/blog/?p=3#comment-4775 Hi Ajmer, I would like to clarify my doubts related to memory. The server is question is Windows 2003 32 bit enterprise Service Pack 2 (physical memory is: 64 GB) and has sql server 2000 SP4 (8.0.2039) 32 bit Enterprise. The AWE and /PAE switch are enabled and the maximum server memory is set to 61440 MB. When I look the Target server memory counter(SQl Server: Memory Manager) in perfmon, I am seeing 33287752 KB (maximum value). I was thinking the maximum value in the perfmon counter referenced here (Target server memory ) should be equivalent to maximum server memory set in server properties as Target server memory is the memory sql server can use. Is that not the case? Can you please clarify? Thanks in advance. Regards, Adam Hi Ajmer,

I would like to clarify my doubts related to memory.
The server is question is Windows 2003 32 bit enterprise Service Pack 2 (physical memory is: 64 GB) and has sql server 2000 SP4 (8.0.2039) 32 bit Enterprise.

The AWE and /PAE switch are enabled and the maximum server memory is set to 61440 MB.

When I look the Target server memory counter(SQl Server: Memory Manager) in perfmon, I am seeing 33287752 KB (maximum value). I was thinking the maximum value in the perfmon counter referenced here (Target server memory ) should be equivalent to maximum server memory set in server properties as Target server memory is the memory sql server can use. Is that not the case? Can
you please clarify? Thanks in advance.

Regards,
Adam

]]> Comment on Identifying the source of SQL Server login failures (18456 errors) by Anonymous http://www.eraofdata.com/blog/sql-18456-login-failures/#comment-4144 Anonymous Tue, 27 Dec 2011 20:49:27 +0000 http://www.eraofdata.com/blog/?p=114#comment-4144 Searched for hours until coming across this entry --- great article! Thank you for sharing! Searched for hours until coming across this entry — great article! Thank you for sharing!

]]> Comment on SQL Server memory configuration by Ajmer Dhariwal http://www.eraofdata.com/blog/sql-server-memory-configuration/#comment-4110 Ajmer Dhariwal Mon, 26 Dec 2011 18:02:10 +0000 http://www.eraofdata.com/blog/?p=3#comment-4110 The max server memory limit defines the size of the buffer pool <em>only</em>. Unfortunately, this does not and can not dictate SQL Server's total memory usage. The MemToLeave section of the post outlines where other processes and objects can use SQL Server's memory, and therefore what to look out on your system to what might be contributing to the memory usage if it continues to increase. If your memory usage increases beyond your max server memory limit added to your memtoleave (384 MB on a typical legacy x86 system) size then it's reasonable to infer you have something leaking memory in SQL Server's address space and take a look a those other processes mentioned that might be contributing to this. It's also worth patching your SQL instance to make sure you're on the latest SP level as it's not unknown for some internal bugs to cause memory leak issues. The max server memory limit defines the size of the buffer pool only.
Unfortunately, this does not and can not dictate SQL Server’s total memory usage.
The MemToLeave section of the post outlines where other processes and objects can use SQL Server’s memory, and therefore what to look out on your system to what might be contributing to the memory usage if it continues to increase.
If your memory usage increases beyond your max server memory limit added to your memtoleave (384 MB on a typical legacy x86 system) size then it’s reasonable to infer you have something leaking memory in SQL Server’s address space and take a look a those other processes mentioned that might be contributing to this. It’s also worth patching your SQL instance to make sure you’re on the latest SP level as it’s not unknown for some internal bugs to cause memory leak issues.

]]> Comment on SQL Server memory configuration by Joan http://www.eraofdata.com/blog/sql-server-memory-configuration/#comment-4107 Joan Thu, 22 Dec 2011 02:35:33 +0000 http://www.eraofdata.com/blog/?p=3#comment-4107 Refer to my post previously, we are using Windows Server 2003 Standard Edition SP2 with 4GB RAM and run SQL 2008 R2. I had set the sql server max server memory to 896MB on 15 Dec 2011. The memory used for sqlservr.exe in task manager are listed below. It is increasing everyday and had exceeded the our setting of sql server max server memory already. 15 Dec 2011: 868,520KB (848MB) 22 Dec 2011: 950,148KB (927MB) (1) Why it will exceed the limit even I had set the limit to 896MB? (2) Will it use up all the available memory of server and lead to machine hanged? Or it will stop increasing up to a specific MB figure? (3) Since the sql server is supporting a 7X24 system, so we cannot stop and restart sql service for reducing the memory used figure. Is there any long term solution can be provided for reducing the memory and keep it in a low figure? Thanks for your help. Refer to my post previously, we are using Windows Server 2003 Standard Edition SP2 with 4GB RAM and run SQL 2008 R2. I had set the sql server max server memory to 896MB on 15 Dec 2011.

The memory used for sqlservr.exe in task manager are listed below. It is increasing everyday and had exceeded the our setting of sql server max server memory already.
15 Dec 2011: 868,520KB (848MB)
22 Dec 2011: 950,148KB (927MB)

(1) Why it will exceed the limit even I had set the limit to 896MB?
(2) Will it use up all the available memory of server and lead to machine hanged? Or it will stop increasing up to a specific MB figure?
(3) Since the sql server is supporting a 7X24 system, so we cannot stop and restart sql service for reducing the memory used figure. Is there any long term solution can be provided for reducing the memory and keep it in a low figure?

Thanks for your help.

]]> Comment on The SQL Server default trace by Ajmer Dhariwal http://www.eraofdata.com/blog/the-sql-server-default-trace/#comment-4106 Ajmer Dhariwal Wed, 21 Dec 2011 22:20:14 +0000 http://www.eraofdata.com/blog/?p=161#comment-4106 This was covered in the last query example (Query 5a: Isolating who made server configuration changes). Just run that and it will show you who did it, as long as it was in the trace file(s) you are interrogating. Thanks for asking the question as it higlighted some strange formatting in this post which I've tried to tidy up in order to make it clearer. This was covered in the last query example (Query 5a: Isolating who made server configuration changes). Just run that and it will show you who did it, as long as it was in the trace file(s) you are interrogating.
Thanks for asking the question as it higlighted some strange formatting in this post which I’ve tried to tidy up in order to make it clearer.

]]> Comment on The SQL Server default trace by Parvinder http://www.eraofdata.com/blog/the-sql-server-default-trace/#comment-4105 Parvinder Wed, 21 Dec 2011 12:34:53 +0000 http://www.eraofdata.com/blog/?p=161#comment-4105 Is there way to see who & when changed the SQL server configuration setting from default trace? setting Like max degree of parallelism, MIN/MAX Memory, Enable/Disable AWE..etc.. Thanks in advance. Is there way to see who & when changed the SQL server configuration setting from default trace?
setting Like max degree of parallelism, MIN/MAX Memory, Enable/Disable AWE..etc..

Thanks in advance.

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