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Opus FAQsManualCommandsObjects 100 percent CPU Utilization



Just noticed this in the last few weeks - not sure if the latest DO update caused this or what but dopus.exe is using 100 percent of one the cores in my i7. I ran procmon on it and there are number of dopus file i/o events that are getting errors.

Process Name: dopus.exe
Path: F:
Operation: FileSystemControl

The drive F: is a fast Intel SSD in RAID0 which may or may not have an effect.

I shut off Norton AV and that didn't make a difference at all.

Any ideas to help fix this? This is extremely annoying.




Disabled all the plugins and it's fine. I don't have any of those file types in the directories so I don't really use/need them anyways.




Can you work out which plugin it was?

If it was the movie plugin then it's probably an issue caused by a 3rd party video decoder that's installed. They're usually behind problems like this (though not always).


It's flaky - I turned them all back on and it's still 0 percent utilization. Definitely better than 100 percent. That makes no sense since that's the only thing I've changed.

I'll post again if I'm able to narrow it down to some other variable.



Okay, the plug-ins are all off an it happened again. Could be SSD related? When I switch back to my normal hard drive the cpu utilization dropped back close to zero. But just to make things interesting, after waiting 5 minutes and switching back to the SSD drive, it's now fine. The only other strange thing was that dopus.exe seems like it's doing something since the CPU utilization is swinging from 80 percent to zero and back and forth. Effectively oscillating. Seems to go on for about 5 minutes then it seems to drop down....

Still looking for a consistent pattern...



Try running Procmon and see if it shows what filesystem access is going on in the background.


Hi Jon,

procmon shows dopus.exe is trying to open/query every single file on the F: drive even though the dual listers only have a couple hundred files visible in them. I exit dopus and kill the dopusrt process and then run dopus again and it seems to be okay. It seems to be doing this several times a day now.



What is the file?

What kind of file is it?

Which operation(s) does procmon report are being done to the file?

Does this only happen when the high CPU usage is also going on, or is it normal and happening even when there isn't a problem?

Is anything else accessing the same file at the same time?

If you right-click one of the operations and choose "Stack", could you post a screenshot showing the Module and Path columns. (That will reveal if a shell extension is likely to be involved with the file being accessed.)


Hi Leo,

It's mostly source code - I wonder if the version control shell extension could be doing this?

Next time it happens, I'll run procmon and see what shell extensions are running.




It's possible the version control extension is involved, yeah. We've seen that once or twice in the past. (e.g. Extensions which keep trying to contact a network server for version control information.)

You can use ShellExView to see which extensions are installed and selectively disable them to see if it solves the problem. With this type of extension, it's best to fully exit Opus and then restart it after enabling/disabling, as the extension may already be loaded in the process when you make the change. (You don't need to reboot the whole system or anything like that, though.)


It's not any of the shell extensions according to the procmon event call stack - looks like dopus.exe is doing something with every file on the drive.



If you turn on Preferences / Miscellaneous / Advanced: no_external_change_notify, does that make the CPU usage and/or the procmon events stop?


Hi Leo,

Makes no difference if it's on/off.




Could you save the Process Monitor log to a PML file, zip it up and send it to me via a private message?