High Disk usage, but low CPU and Memory Usage

jmt356
SilverLounger
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Joined: 28 Mar 2010, 01:49

High Disk usage, but low CPU and Memory Usage

Post by jmt356 »

What does it mean when Task Manager shows very high Disk usage (e.g., < 90%) but very low CPU usage (e.g., > 5%) and low Memory usage? My laptop consistently shows high Disk usage but low CPU and Memory usage when it is in an idle state without any programs being actively used, though there are background processes running.

What is Disk usage, anyway? Is that referring to the hard disk?
Regards,

JMT

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HansV
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Joined: 16 Jan 2010, 00:14
Status: Microsoft MVP
Location: Wageningen, The Netherlands

Re: High Disk usage, but low CPU and Memory Usage

Post by HansV »

Yes, disk usage refers to reading from the hard disk and writing to the hard disk.
Recent versions of Windows automatically perform maintenance tasks from time to time. It is very well possible that these tasks use little CPU capacity but generate a lot of disk activity.
Regards,
Hans

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Jay Freedman
Microsoft MVP
Posts: 1140
Joined: 24 May 2013, 15:33
Location: Warminster, PA

Re: High Disk usage, but low CPU and Memory Usage

Post by Jay Freedman »

Run the Windows Resource Monitor (resmon.exe, which you can start from the Run box, or from the Performance tab of the Task Manager). Go to the Disk tab. In the Disk Activity section of the page, click the column header of the Total column to sort the processes with the highest read/write rates to the top. Looking at the entries in the File column should tell you what's using most of the disk activity.