Seeing unexpected write IO in Activity Monitor, had a look with:
sudo iotop 2>/dev/null
And lssave is the culprit. Then you want the following:
sudo /System/Library/Frameworks/CoreServices.framework/Versions/A/Frameworks/LaunchServices.framework/Versions/A/Support/lsregister -kill -r -domain local -domain system -domain user
Or a more verbose:
sudo /System/Library/Frameworks/CoreServices.framework/Versions/A/Frameworks/LaunchServices.framework/Versions/A/Support/lsregister -kill -r -v -lint -domain local -domain system -domain user 2>&1 | grep -v 10811 | grep -E -B 1 -A 2 "Can't|Error"
Simon Major’s Blog 