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100% cpu usage with windows 7

Posted: 24. Aug 2012, 18:34
by immerso
Hello,

I have 2 virtual machines running on a Intel Core2 Duo E8200 @2,66GHz 64 bit System with 8 GB RAM (no pagefile) with Windows 7 Professional as host.
Each VM has 2GB RAM and uses 1 cpu core (100%), the guest OS is also Windows 7 Professional.

The problem is, that after some time, both VMs have 100% CPU usage - and there is no explanation, they should be in idle state.
I did not made any special configurations which could explain it and at least in one VM, there is no service or application that could cause the cpu usage - the task manager showed svchost.exe and the idle process.

Are there any known problems that cause such problems? I try to investigate it further - strangely, it seems to occur only after a certain time since the lasr reboot passed. Energy options are all set to "never".

Best regards
immerso

Re: 100% cpu usage with windows 7

Posted: 26. Aug 2012, 23:37
by Andre.Ziegler
idle is fine. run ProcessExploer and look at the callstack which service causes the CPU usage. ProcExp shows the tag of the service. My guess is that Window checks for updates and run the optimization (defrag).

Re: 100% cpu usage with windows 7

Posted: 28. Aug 2012, 12:12
by immerso
The first problem is, that I cannot access the VM anymore, now that it is on 100% cpu usage, neither via RDP, nor directly. The machine does not react anymore, not even to "shut down via ACPI", only to a hard reset. The host is also on 100% cpu usage, so it is difficult to perform any tasks, and other services of the host are affected, too.
Windows updates should be searched (but not installed!) at 3 am in the night - but the problem occures in the fore- and afternoon. I disabled the automatic defragmentation, so that cannot be the problem anymore. The last time I could log in, the process explorer just showed "85% idle process".

It's also interesting, that I have two VMs, but currently, only one is at 100% cpu usage. I reset the machine, and now it hangs during the start up screen "Windows starts" ("Windows wird gestartet" in German). After another hard shut down and start up, it runs again. I could not find any planned tasks that run in the last 24 hours.

Re: 100% cpu usage with windows 7

Posted: 28. Aug 2012, 12:44
by mpack
Please post a VM log file, as a zipped attachment.

Re: 100% cpu usage with windows 7

Posted: 8. Sep 2012, 12:56
by immerso
The log file directory is attached (all 4 files, but only VBox.log is current), from my machine named VM1. Currently, the machine is again at 100% cpu and I am unable to connect to it.