Recently I have mentioned that my Mac is unusually busy, even when I am not compiling code, but just browsing of Internet or files. Running Activity Monitor - it was showing Finder on top, almost all the time consuming 100% of CPU. Event with 2 cores - Mac was struggling with some simple tasks.

I thought at this moment - I cannot believe I will have the same stupid stuff like on Windows, when there is some missing Network Resources. When browsing and googling for the answer, I have found lots of suggestions in this area, but most of them were posted at least 2 years ago for much older versions of MacOS. Well - I have decided to solve it myself.

Command:

lsof | grep Finder

Did not help much. There were some strange entries leading to “/dev/null”. So I have made shot in the dark. I went to my Finder view options and found my problem. Some time ago I have been browsing my HDD trying to identify how to free some space. I used the function of Finder to show the size of Folders - this is quite consuming operation, especially if it have to be calculated for many folders, subfolders, sub-subforders… When you keep finder open with such a view - it refreshes it almost on every file operation on the tree - and this was my CPU bottleneck. Problem solved:

Open finder. Press Cmd+j (View -> Show view options) and set the flag “Calculate all sizes” to OFF: