Windows 7 System process reading/writing like crazy

Use xperf from the WPT (part of the Windows 8 SDK) to trace disk IO:

http://blogs.msdn.com/b/ntdebugging/archive/2009/08/17/xperf-to-investigate-slow-i-o-issues.aspx

Run the script, minimize the CMD Window and when you have the issue again, go back to the cmd, wait 15-20s, press a key to stop logging. Open it with xperfview and look in the Disk IO graph which files the SYSTEM process writes/reads.

I had a similar problem. For me the trigger was opening IE10 (why would I use IE? I don't even know). The System process would hit the hard drive incessantly. It wouldn't freeze everything but it made the computer effectively unusable with an average disc response time of 10,000+ms.

I found the fix at Serverfault: System process (PID 4) constantly accessing the hard disk. My summary below:

The problem is windows update. When certain programs are started, for me it was IE10, or intermittently the system will check for updates. It takes some time and locks up the machine. To fix: deactivate updates, first for the running programs. If the problem persists, consider deactivating windows updates.

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And also, this AdskScSrv.exe process makes lag too. It's from autocad, the services is "Autodesk Licensing Service"

Yes I just remove that services.

Steps: 1. Start 2. type "msconfig" and enter 3. goto Services tab and find "Autodesk Licensing Service" (make it easy by sorting the name) 4. Uncheck then click apply. and restart now if you want

http://www.cadforum.cz/cadforum_en/qaID.asp?tip=3707

For me it was: sharing the whole drive (C:) into network.

And when I delete that sharing rule, well it works and run normally.

To do this (Win 7, believe similary in Win 8):

1. Right click on Computer and select "Manage"
2. In the left explorer choose "Computer Management (Local)" => "Shared Folders" => "Shares"
3. You will see Folder Path, which is the path you share to your network.
4. In my case, I was sharing C:\
5. So I delete this rule, "Right Click" and choose "Stop Sharing"

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