In OS X Mavericks, com.apple.IconServices seems to be causing almost 100% CPU usage and is causing Finder to become unresponsive (the "beach ball"). This happens periodically, usually when accessing a directory in Finder for the first time in a while. Restarting Finder stops IconServices from eating all the CPU, but revisiting the problem directory makes the problem happen again. How do I solve this?
Apple user Kieran Healy has apparently solved the root problem and come up with a fix, described on his blog here. The short of it is to open Terminal and then enter the following command:
Apparently, IconServices was seeking a directory and, failing to find it, began thrashing. Kieran's fix creates that directory.
When I tried this solution, the fix was immediate -- that is, no restarting, relaunching, or even re-visiting of directories was required.
All credit goes to Kieran Healy for this fix. I suggest visiting his website and giving him a "like".
This blog post shows how to find out exactly what IconServicesAgent and coreservicesd are up to when they're thrashing your Finder.
In a nutshell, grep the output of fs_usage to find out what files are being icon-serviced all the time. Specific command lines are given, and the files that were causing their problems are the same ones I'm seeing.
The fs_usage invocation is a valuable diagnostic tool, especially if your problem isn't quite the same.
If this works for people, please pass the message on to this related question. I don't have the reputation to answer it myself.