Disk thrashing on initial starting of Directory Opus


I have reinstalled my Windows 7 Ultimate SP1 and Directory Opus (I know, its old). On initially starting Opus it thrashes the hard drives for perhaps 2 minutes. The old installation never did this. I know it is Opus causing the disk activity, as it immediately ceases if I close Opus.

Does anyone know what may be causing this behaviour please?

Thank you.

My guess is you have a large set of file collections whose details are being refreshed.. (Something that's handled better in more recent versions.)

It could also be automatic folder size calculations turned on and triggered for a drive with a lot of files and folders.

If it isn't those, a tool like Process Monitor can show you what is being accessed, which usually indicates what's going on.

Hello Leo,

Thank you for getting back to me.

I have no file collections defined, but lots of files. I have always had automatic folder size calculations turned on, but the previous Opus installation did not do this. In fact, Directory Opus itself should be set up exactly the same way as it was before, and I believe Windows is also.

I have downloaded Process Monitor at your suggestion. It is going to take me a while to work out how to use it, as it supplies lots of information at an astonishing rate. To test, I set a filter to only monitor the process dopus.exe, and started and ran Directory Opus for 10 seconds. It recorded 393,795 events (by dopus, in 10 seconds). And it didn't even do its disk thrashing behaviour at the time! How can it possibly be doing so many things when I had not even selected a file or looked at a different directory? Is this normal? It was just sitting there.

Further suggestions or guidance would be much appreciated.


Just a reminder: don't forget to filter only the disk access events in the Process Monitor (if you didn't already), because by default it shows huge amount of non-disk related stuff (such as threads creation/termination, registry access etc.)


If you hover over those buttons, it should display a tooltip saying what they toggle, so disable all except the "Show File System Activity" (second from the left).

Also use Ctrl+X to clear all the entries (so for example clear all before you go accessing your files in Opus). I recommend you do this before toggling the above mentioned filters since it will be faster.

It's probably normal, although I couldn't say for sure without seeing what the events are. But computers do a lot of things very quickly, and there's a constant stream of activity from lots of processes even when you aren't doing anything with the computer. :slight_smile:

Automatic size calculation will cause a lot of disk access if you point Opus at a folder with lots of things below it. Windows and NTFS are quite inefficient when it comes to reading directory listings.

See Process Monitor instructions for guidance.

Thank you bytespiller and Leo,

I seem to have solved the problem and yes, it was my fault. My new installation of Opus was exactly the same as my previous one, but the hard drives were not. I run Opus with four tabs that open to specific locations on my hard drive array. Not all of the drives are yet installed, and the drive letters have changed. A couple of the directories the tabs pointed to now do not exist.

I changed the tables to point to a location that does exist and resaved my default lister. It has not thrashed the hard drives on starting since. I conclude that Opus was looking for the target directories to which the tabs were set.

Thank you again. Your time and efforts are greatly appreciated.


It's strange if that alone fixed things. Trying to display paths that don't exist should not cause much disk access at all.

Hello Leo,

That's all I corrected and thus far, it does seem to have fixed it. I don't know what it was actually doing, but it sounded like it was looking at every file on every disk, individually ... haha

Should I be worried that there may be something wrong with my installation?