This article describes an update for Windows Server 2012 R2 to that reduces the time that is required for "List Disks" and "List Cluster Disks" in Windows cluster validation.
To resolve this issue, install update 2955164. For more information about how to obtain update 2955164, click the following article number to view the article in the Microsoft Knowledge Base:
2955164 Windows RT 8.1, Windows 8.1, and Windows Server 2012 R2 update rollup: May 2014
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
For more information about software update terminology, click the following article number to view the article in the Microsoft Knowledge Base:
824684 Description of the standard terminology that is used to describe Microsoft software updates For example, it may take 2 hours for 240 iSCSI disks originally. After applying this update, it only takes 2 minutes.