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显示标签为“memory”的博文。显示所有博文

2012年3月20日星期二

any way to prevent SSAS memory from paging?

This morning msmdsrv.exe looked like the following in Task Manager:

Memory Usage: 600,000 K

VM Size: 2,500,000 K

If I understand correctly, that means that a good deal of SSAS memory has been swapped to disk by the OS. Is there any way to prevent this? (I have read about using the Lock Pages In Memory privilege at http://msdn2.microsoft.com/en-us/library/ms179301.aspx which lets SQL prevent the OS from paging sqlservr.exe memory. I don't suppose there's an equivalent SSAS setting.)

In particular, the symptom I'm seeing is that after we finish processing, all that paged memory has to be loaded back into memory before the transaction can be committed. Committing the transaction is usually very quick. But when most of the SSAS process memory is pages, it takes quite a while, during which I can see the Memory Usage number in Task Manager growing. (I don't think it's a blocked transaction commit.)

Looks like maybe there is a way to do this in SP2. Can anyone explain the PreAllocate setting further?

http://www.sdsqlug.org/presentations/November2006/November_2006_64-bit_SQL_Server.pdf (page 36)

2012年2月18日星期六

Any good link on tracking memory issues

I have always found it hard to figure out if SQL has memory issues using
tools like perfmon,etc..
Its easy for CPU and IO i.e. high CPU or disk queue, but could never figure
out how to go about memory.
Yes some may say look at DBCC memorystatus,etc.. but that things greek ;)
Can someone help or maybe theres some documentation that talks about
tracking memory usage,etc. for SQL Server..Hi Hassan,
Two excellent sources I know are:
Paper "Troubleshooting Performance Problems in SQL Server 2005"
http://www.microsoft.com/technet/prodtechnol/sql/2005/tsprfprb.mspx
Chapter 1, book "Inside SQL Server 2005: Query Tuning and Optimization"
by Kalen Delaney, et al.
Hope this helps,
Ben Nevarez
Senior Database Administrator
AIG SunAmerica
"Hassan" wrote:
> I have always found it hard to figure out if SQL has memory issues using
> tools like perfmon,etc..
> Its easy for CPU and IO i.e. high CPU or disk queue, but could never figure
> out how to go about memory.
> Yes some may say look at DBCC memorystatus,etc.. but that things greek ;)
> Can someone help or maybe theres some documentation that talks about
> tracking memory usage,etc. for SQL Server..
>
>