FSRM: Alternate data streams should be large enough to store classification properties

Updated: August 31, 2012

Applies To: Windows Server 2008 R2, Windows Server 2012

This topic is intended to address a specific issue identified by a Best Practices Analyzer scan. You should apply the information in this topic only to computers that have had the File Services Best Practices Analyzer run against them and are experiencing the issue addressed by this topic. For more information about best practices and scans, see Best Practices Analyzer.

Operating System

Windows Server 2008 R2, Windows Server 2012


File Services






The alternate data stream size is too small to store classification properties.


File Server Resource Manager will reclassify files every time Windows or an application queries the classification of a file. This will result in reduced performance for applications, file management tasks, and reports that query classification properties for files.


Use Registry Editor to increase the size of the alternate data stream cache.

To increase the size of the alternate data stream cache by using Registry Editor

  1. Open Registry Editor.

  2. Locate and then click to select the following registry subkey: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\SrmReports\Settings.

  3. If the MaxCacheSize setting does not exist, proceed to the next step. If it does exist, proceed to step 6.

  4. On the Edit menu, point to New, and then click DWORD Value.

  5. Type MaxCacheSize, and then press ENTER.

  6. Right-click MaxCacheSize and click Modify.

  7. In the Value data text box, enter the maximum number of bytes for the cache, and then click OK.


The default value is 4096.