Excessive Memory Usage on Windows machines

Article Number: 
304

Summary:

In some rare situations, a Microsoft Windows system may consume excessive amounts of memory. This can cause system performance issues and, in extreme cases, a crash of the system. The problem can have the appearance of a memory leak, with the memory not obviously tied to a process when viewed in Windows Task Manager. StorageCraft has seen this in a very small number of cases with ShadowProtect and ImageManager. Stopping the application or service may result in an instant memory usage drop, which may give the incorrect impression that it is a problem with the application or service when it may be caused by a bug in the Windows operating system. 

Information:

This problem appears to be rare and may be triggered by a whole range of different situations including reading or writing large files over a network connection, or even from some local disks. In addition, while this condition can occur with a wide range of applications, it may not occur with all applications, even if they perform similar functions. So simply copying a file may not trigger the problem but a read of that same file may cause the issue.

Hardware problems or configurations may exasperate the issue further. For example, disabling the ‘Write Through’ option on some RAID controller cards can make the problem much worse as data is streamed to the local disk. This can seem counterintuitive because a RAID with multiple drives should support fast write speeds and high I/O– both of which should limit the need for caching. We have seen this issue on some high performance systems.

The workaround provided by Microsoft is a HotFix that contains a Windows Service called “Dynamic Cache Service (DynCache)”. DynCache may be downloaded for a number of different versions of Windows operating systems and allows the user to set the maximum amount of memory used for Windows caching. This setting is in the Windows Registry.

The Microsoft article found at : http://support.microsoft.com/default.aspx?scid=kb;EN-US;976618 provides more information about the fix. Unfortunately, the version of DynCache listed in the article does not support Windows Server 2008 R2. We recommend in these situations you contact Microsoft support directly to obtain the HotFix. If you have any problems obtaining this fix, please contact StorageCraft support.

Please note: The foregoing HotFix and workaround are both provided and recommended by Microsoft. StorageCraft therefore makes no warranty about the effectiveness or suitability of this fix and similarly assumes no liability for issues or problems resulting from application of the fix. Its use is at the sole discretion of the end user. The details provided here are for information purposes only and we recommend the user contact Microsoft if they have any additional questions or concerns.