After defragging a 320 Gb 2,5" drive with an os on it through another computer, since it left some red squares (so it didn't defragged the whole drive) I decided to switch on the "Move large files to end of drive during whole drive defrag" and re-defrag the drive.
So it started and after a while it reached 75%, and after clicking one of the red squares it listed what files and folders belonged to it, and by mistake I clicked on one of the column top side, that switched the order by that column, so to block the mistake I tried to close the file list tab, but then Defraggler stuck and/or froze, not responding at any command (but on task manager I see it still working or doing something).
Actually I didn't kill the task since it was defragging and I'm afraid it would mess with the data on the disk. So, since I have an i7 920 (quad core hyperthreading, on 6 gb ram) I set Defraggler to use 4 logical CPUs while all the other tasks to the other 4, where possible, and I also rised its priority to "High" (I also tried "Real time" but it seems to rise all the cores, real and virtuals, to high usage).
I hope it would unstuck itself after ending doing what is supposed to do, but after several hours it seems to keep stuck.
It uses the Microsoft Defrag API and when running on a hard disk with the NTFS file system "it shouldn't in theory cause corruption" if for instance there's a power outage, the machine decides to hibernate/sleep/turn off, or if the user kills a defrag process. Although I wouldn't kill the process and instead would let it finish normally to play on the safe side.
If you do kill the defrag process run ChkDsk on the drive afterwards before doing anything else with the hard disk.
After 21 hours, 30 minutes and 49 seconds of CPU time (it shows 21:30:49 on task manager), and now not showing any CPU activity, it seems to have ended what it was doing, even tho it's still frozen/stuck and not responding.
Maybe now it's safe to guess it could be killed without any consequences.
Well, ok, I'll try it, hoping for the best.
I'll keep finger crossed <span class="ipsEmoji">?</span>
Wish me luck <span class="ipsEmoji">?</span>
I did it, and it seems that all went well, chkdsk didn't find any error.
I launched Defraggler again and it showed me the job done, all the large files are at the end of the partition.
Thanks anyway for your answer.
Bye <span><img alt=":)" data-emoticon="" height="20" src="<fileStore.core_Emoticons>/emoticons/default_smile.png" srcset="<fileStore.core_Emoticons>/emoticons/smile@2x.png 2x" title=":)" width="20"></span>