Disk Defragmenter Polling Causes Excess Disk I/O on Drives with Unformatted Partitions (244746)



The information in this article applies to:

  • Microsoft Windows 2000 Server
  • Microsoft Windows 2000 Advanced Server
  • Microsoft Windows 2000 Professional
  • Microsoft Windows 2000 Datacenter Server

This article was previously published under Q244746

SYMPTOMS

When the Windows 2000 Disk Defragmenter console (Dfrg.msc) is active, you may notice that excessive disk input/output (I/O) activity occurs every few seconds on one or more drives, even when no defragment or analyze operation is in progress.

CAUSE

The Disk Defragmenter tool polls all drives every few seconds to refresh the list of available volumes to defragment. When a drive contains unformatted partitions, the polling thread causes Windows 2000 to interrogate the partition further to determine whether it contains a recognizable file system to mount and add to the Disk Defragmenter interface. This reoccurs every few seconds.

This behavior is more noticeable with a large number of unformatted partitions on a single drive.

RESOLUTION

To work around this behavior, make sure that all of your disk partitions are formatted, or delete any unformatted partitions that are not immediately necessary.

NOTE: This behavior occurs even if the unformatted partitions do not have drive letters assigned.

STATUS

Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article.

MORE INFORMATION

The excess disk I/O may continue if you used the Computer Management snap-in to start the Disk Defragmenter tool originally, but the Computer Management snap-in is now focused on another tool. This behavior occurs because the Disk Defragmenter code is still active in the background. You must quit the Computer Management console for the Disk Defragmenter code to be removed from memory.

NOTE: Although the Disk Defragmenter console makes this excess disk I/O apparent by polling every few seconds, the same excess disk I/O can be triggered when you are performing other tasks (such as starting Windows Explorer) if you have a large number of unformatted partitions.

Modification Type:MajorLast Reviewed:11/21/2003
Keywords:kbprb KB244746