The last few days I have been performance testing one of our websites due to a severe performance drop after migrating to a new VMware hosted environment. Admittedly the application is not a great perfomer anyway (due to IMHO major overspeccing on the application security) but there was a significant drop in performance that was causing users (and us) grief.
It turned out that IBM director was using about a constant 30% CPU whilst the box was doing anything and even though it never actually reached 100% the user experience was that of a box under full load. Once it was disabled/uninstalled the box went back to normal.
TBH this was prob an oversight on the person doing the P2V but uninstalling obsolete software is something that really should be done as a matter of course!!