lsof - high cpu parent process adobe reader and acrobat
I recently updated my late 2010 macbook air to mavericks and noticed some stuttering during youtube videos. I checked activity monitor and found a high cpu process periodically running with a process name of "lsof" with a parent process of "adobe reader and acrobat". Killing lsof didn't work - it would restart very quickly. Killing the adobe process stopped this and cleared the stuttering youtube videos.
Peter