Hi all,
this forum is full of reports that Defraggler is slow and/or creates a lot of CPU usage while having close to no disc activity. Inexplicably to the present day this issue is still not fixed, despite the cause seems quite clear. Therefore I'll try and report again and hope that this time something good comes from it:
The issue happens whenever defragmenting a drive with many small files.
It happens with normal "Defrag" operation (not with "Quick Defrag" or when defragging files from "File list", at least it's by far not as severe with those operations)
The actual slow part - and therefore the bottleneck of the defrag operation - is the part where Defraggler decides where to put a file. One can clearly see in task manager that CPU load for one core is nearly constantly at 100% (that is e.g. 50% total CPU load on my dual core machine). Then for a very short moment (when the file is actually moved) CPU load drops a little, only to rise again as soon as Defraggler starts to compute the best place for the next file.
CPU load is exclusively created by "Defraggler.exe" (or "Defraggler64.exe" respectively). There is no anti virus software interfering (I have even turned it off just to be able to eliminate is as a cause). There is absolutely no other disk activity during this time. There are no backup solutions interfering (I completely disabled SystemRestore / VolumeShadowingService and the like). It's just Defraggler!
Therefore it seems obvious to me that the algorithm that determines where to put files is simply too slow and needs to be improved!
Just to clarify the severity of this issue: When I defrag my hard drive there's only about one write operation every five seconds (for files with only single digit KB sizes)! You can probably come up with an estimate on how long it takes to move several thousand of files during a full defrag yourself...
A little bit of system information:
- OS: Windows 7 Professional x64
- CPU: Intel Core2Duo P8400 (2 x 2.26 GHz)
- HDD: Seagate Laptop Thin SSHD (ST500LM000);
same issue with a Western Digital Scorpio Blue (WD2500BEVT) which I had installed before
- Defraggler: v2.18.945 (64-bit, same issue with 32-bit version though)