Fragmentation caused by new optimization methods

[Soichiro]

Just like the topic says, I ran Jkdefrag -a 8 on my hard drive which had just been defragmented, and by the time it was done, there was a very large amount of yellow on the disk map, indicating a large amount of fragmentation. I'd say about 25-30% of the non-free space on the disk map was yellow, whereas it was under 1% before. I don't know if it's supposed to be like this, but if it is, that seems like a very bad set of optimization methods. Running it on -a 3 again gets rid of the fragmentation, but I'm sure it got all the files out of order too.

[JDPower]

This is normal. From the homepage:

All the sorting options will "wrap around" unmovable files on disk by splitting regular files into fragments. This may seem strange for a defragmenter, but the fragments are aligned and therefore have a very small impact on performance. It looks terrible on the screen and in the statistics, but no worries.

I'm not too keen on it (ie running a defragger and getting more fragmentation) but Jeroen is far more knowledgeable than I and I'm sure he wouldn't have it work that way if it was a bad thing.

[Joel Low]

Apparently only the first 4 -a options will give an unfragmented disk, but I quote the main page:

Sorted optimization
    These optimization strategies are for incidental use once in a while. They take a lot of running time and data movement because they rewrite all the data on the disk. The strategies vacate a small area on disk and then fill it up again with the files in the selected order.

        * Sort by name: very good for fast program starting. The files used by a particular program will be very close together on disk.
        * Sort by size: placing all the small files together at the begin of the disk will dramatically reduce the average file seek time.
        * Sort by last access: files that have not been accessed in a while are probably unimportant and are best sorted to the back.
        * Sort by last change: placing files together that change a lot (for example databases and logfiles) will speed up regular operation of the system.
        * Sort by creation time: The oldest files on the disk are likely to be important system files, for example used when Windows is booting.

    Note: all the sorting options will "wrap around" unmovable files on disk by splitting regular files into fragments. This may seem strange for a defragmenter, but the fragments are aligned and therefore have a very small impact on performance. It looks terrible on the screen and in the statistics, but no worries.

[jeroen]

I have now released version 3.14 with even more explanatory notes on the homepage. I can understand the confusion and worries, but the fragments are by design!