Comodo AV and defrag

Running product version 5.9.221665.2197. DB 11704. Windows XP SP3 Home.

Have had a problem for some months now that when I attempt a Windows defrag, it takes ages and ages and normally grinds to a halt with an error. Defrag runs fine in Safe mode and Contig runs fine as well. I have also been trying to work out why the PC has slowed down as well. I have resolved this by removing Kontiki and all its bits but stiil no joy with the Defrag. For the last Defrag I opened the Widows task manager and found CMagent competing with the defrag file for processor time! Going to the Comodo AntiVirus tab and changing the real time scanner to DISABLED was an instant winner. The defrag file increased its use of the processor time and the defrag finsihed OK.
Is there a setting that I can change so I don’t have to stop the AV when doing a defrag or is this a “feature” of the latest software that only shows up on slower processors?

i think the problem is that comodo antivirus trying to scan all the files the defrag program is accessing causing high cpu usage. i think your best bet would be to disable the AV while you defrag.