Windows 7 and its System process hogging up the CPU

Posted January 14th, 2010 by Wesley

If you’re running Windows 7 and find that from time to time, you PC slows down for 5-10 seconds, try to monitor the System process (NT Kernel & System, or ntoskrnl.exe): chances are that this process is hogging the CPU.  If it is, take a look at your network adapter(s) properties and check if LMHOSTS lookup is enabled.

Apparently, there is a bug in the kernel when looking up the LMHOSTS table, causing the CPU to enter a semi-infinite loop. Semi-infinite, because the thread times out after a few seconds.

For more information, look here (original forum post) and the KB article at Microsoft (more specifically, workaround #2).  Although the KB article is originally for Windows Server 2003 platforms, it also applies to Windows 7, just don’t try to install the hotfix on you Windows 7 machine!

Tags: cpu, kernel, lmhosts, performance, system, windows 7