High Paged Pool RAM Utilization on Systems Running Rapid Recovery (4035226)

You are experiencing Rapid Recovery using an overwhelming majority of the memory on the Core machine (90%+).

By default, Rapid Recovery uses Windows write caching to improve performance of writes to the repository. However, in some core systems (primarily Server 2008) write caching may prove detrimental to performance as Windows is not able to properly keep up with the amount of cached writes. Hence the systems memory fills up with cached writes that are slowly being committed to disk. Once the memory is filled up all Core functions begin to operate slowly as they must struggle to acquire memory to perform tasks. By disabling write caching we improve the overall performance of the Core server by freeing up memory.

To resolve this issue, change the write caching policy.  To change the write caching policy for a repository to off and reclaim the memory that was being used:

1. Stop the core service gracefully
2. Open regedit and browse to the registry folder HKLM\Software\AppRecovery\Core\Repositories\\FileConfiguration\X\Specification\
   
   where:
   X will be different for each repository
   X will be different for each extent
3. Change the registry key WriteCachingPolicy to decimal value of 3
   1. When the WriteCachingPolicy is 2 (ON), means Windows controls the write caching. Setting the write caching policy to ON can result in faster performance, however, the recommended setting is OFF
   2. The recommended WriteCachingPolicy is 3 (OFF), which disables Windows write caching, thereby enabling Rapid Recovery to control the write caching. Rapid Recovery will use write caching to ensure that the repository isn’t flooded with more incoming data than outgoing traffic
   3. If set to 4 (Sync), Windows controls the caching as well as the synchronous input/output. It has been proven beneficial to set the WriteCachingPolicy to Sync while troubleshooting issues related to performance or application crashes during the execution of a specific task.
4. Make this change for each extent in each repository
5. Download RAMMAP from Microsoft – RAMMap - Windows Sysinternals | Microsoft Docs
6. Using RAMMAP empty the Standby List to free up all standby memory
   1. Open RAMMAP
   2. In the menu bar choose Empty -> Empty Standby List
   3. Refresh RAMMAP by choosing File -> Refresh
   4. You should now see a considerable change in the amount of memory used
7. Start the core service.

Note: Please do not change the WriteCachingPolicy to 3 for the repository extension, that is residing on the storage with non-standard bytes-per-sector value. The standard value is 512. Otherwise, repository will not mount.