Memory manager pages out all processes to under 1 MB while server "hangs" RRS feed

  • Question

  • Hello.

    SBS 2003 Sp2,  Exchange 2003, SQL 2000 and 2005 Express.

    4GB of RAM

    2 ea Intel Quad Core Processors 2.33 Ghz

    3 Mirrors running on Dell PERC

    We installed a new line of business app that spec'd SQL 2005 or 2008 Express. So, we installed 2008 Express, which broke our 2005 installs. We uninstalled 2008 and 2005, and re-installed 2005, which re-enabled functionality with the apps that need 2005 fine. We also installed a new instance of 2005 Express.

    After installing this, we noticed that the server now ran with over 1.5 to 2 GB of free RAM, where previously it would run with 200 to 400 MB free, which is 5% to 10% free which is within specs.

    We started experiencing temporary network disconnect notices, which finally we were able to find that the real issue was that the whole server was hanging while excessive paging was happening.

    Upon further examination, we found that the server, when it still has 1 GB to 1.4 GB of free memory, will suddenly start paging the running processes out of RAM. These process include SQL, Store.exe and other processes, which normally run with over 100 MB in physical memory.

    For example, one SQL may be running with 280 MB of Ram, Store.exe with 170, along with other processes. When the paging starts, I found that SQL instance, for example, brought down to about 500K, along with other processes. When the paging and server "hang" stops, these processes quickly start taking up more physical Ram and return to more normal levels. At some point while the server still has 1 to 1.4 GB of physical Ram free, this process wil begin again.

    The page file has plenty of room free, and also I increased the size with no results, and also set it to system managed with no results. It is now running at apprx 75% free.

    I checked registry entries for PagedPool Usage, Size, and SystemPages and set to Microsoft recommended values.

    I have monitored the system for max memory values, and there is no user process that is peaking to max out the memory to cause this. The server does have plenty of Ram free, but goes through this process.

    SQL instances are set to 256 MB, 128 MB and other small size limits.

    We do have two VMWare VM's running with memory set to a hard 512 MB for each, set in the VMWare manager to not get paged out. When the issue happens, these also get paged out and reduced in size.

    I have tried running the server without the VM's running, same issue.

    Are there some other settings that would pertain to determining when the server clears physical memory or why the server pages out the processes like this?

    All help is greatly appreciated.

    I am adding the following info:

    Following are the results of some monitoring on the server:

    Max values for Shared system memory:

    911 MB Total

    CacheBytes 526 MB
    Pool Nonpaged bytes 118 MB
    Pool Paged bytes 263 MB
    System Code Total 1 MB
    System Driver Total 3 MB

    I am not using any special switches in the boot.ini such as /3GB or any other switch. Boot.ini is SBS2003 standard switch as installed.

    Also just noticed that the Working Set peak is 5.95 GB, running is 1.04 GB. Commited Bytes maximum is 4.3 GB.



    • Edited by KTSaved Monday, December 13, 2010 2:22 PM Add additional info
    Monday, December 13, 2010 1:18 AM

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