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JaybeeSQL
Posting Yak Master
112 Posts |
 Posted - 2013-02-25 : 07:28:08
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| Hi all,Got a problem with PLE that I'm not certain how to diagnose....My monitoring software reports intermittent numbers from 130-180, well below the MS recommendation of 300. It hits this 10-15 times every day, at random intervals. Our Buffer/Procedure cache hit ratios % are both in the high 90's, which is consistent with our data being lightly transacted (although this is a log shipping primary)Server spec is:SS EE (32bit) 64Gb Ram.Any way to tell if this is a problem, or threatens to become one?Cheers,JB |
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jackv
Master Smack Fu Yak Hacker
2179 Posts |
Posted - 2013-02-25 : 07:46:07
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| the key with Page Life expectancy is consistency. If it's consistently low than that is a good indicator more physical memory is required. In your case it's intermittent , so : check fo rmissing indexes, updated statistics and indexes missing statistics first. Does this alleviate the problem?Use a measurement , for example, over 10 minutes on a represntative workload and check the PLEJack Vamvas--------------------http://www.sqlserver-dba.com |
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JaybeeSQL
Posting Yak Master
112 Posts |
Posted - 2013-02-25 : 09:50:41
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| Updated stats, and indexes missing stats - are these two separate things? |
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jackv
Master Smack Fu Yak Hacker
2179 Posts |
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chadmat
The Chadinator
1974 Posts |
Posted - 2013-03-09 : 17:40:22
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| Also,300 is far too low a threshhold for the size of your Buffer Pool (Assuming you have the lion's share of that 64GB dedicaated to this instance). And 32 bit still??? -Chad |
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James K
Master Smack Fu Yak Hacker
3873 Posts |
Posted - 2013-03-10 : 13:03:15
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| Might seem like a silly question, but you do have AWE enabled, don't you? Are you on Server 2003 or 2008? |
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JaybeeSQL
Posting Yak Master
112 Posts |
Posted - 2013-03-11 : 05:51:55
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| 2K3, AWE enabled. Moving the OS estate (well over 100 servers) to 64bit would cause an upheaval of colossal proportions, given how tightly regulated and scrutinised our environment is. |
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jackv
Master Smack Fu Yak Hacker
2179 Posts |
Posted - 2013-03-11 : 11:44:49
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| AWE is not required in 64 bit , but you may want to consider Lock Pages in Memory .This will depend on different scenarios. The main benefit of turning it on is that the buffer pool buffer doesn't get paged out.Jack Vamvas--------------------http://www.sqlserver-dba.com |
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chadmat
The Chadinator
1974 Posts |
Posted - 2013-03-11 : 19:23:59
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| What is Total Server Memory and Target Server Memory in perfmon?Also, can you corrolate the drops in PLE with any large reporting queries or anything like that? -Chad |
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Low Page Life Expectancy