Drive map exhibits strange behavior

[bmore]

I just replaced the hard drive in my laptop with a WD Scorpio Blue AFD 1TB, running three primary and four logical partitions. The first thing that I noticed is that whenever I defrag the 400GB logical partition, haven't tried other partitions yet, that the drive map seems to freak out. Defraggler shows Defrag Complete 100% and is still running, when suddenly the drive map's freespace changes to massive amounts of not fragmented low occupancy blocks, staggered by remaining freespace. What makes this even more unusual is that the freespace is broken on a diagonal with each row below offset to the right by an increment of +1. It kind of looks like stacked ledges, or really wide stairs from an old 2D scroller. It does revert back to normal just before defraggler stops defragmenting, and so far file integrity is fine. I did check and verify that system restore was not active on the partition, and that VSS disable was checked in Defraggler. So since this is a repetitive behavior, and I can't determine the cause on my own, I decided to report it as a bug.

[bmore]

Some more information on just what I've tried to do to resolve the display map issue:

 

Laptop:

AMD TL-58 x2

4 GB DDR2 RAM

WDC Scorpio Blue 1 TB AF (Advanced Format, 512E, or 512e) Hard Drive

Windows Vista Home Premium 32-bit with Service Pack 2

 

Partitions (by physical order):

Primary, FAT32, Semi-hidden (Partition ID=27), 9.77 GB (6.27 GB used)

Volume C: - Primary, NTFS Compressed, Home Premium SP2, 69.65 GB (32.96 GB used)

Volume D: - Primary, NTFS Compressed, Backup Partition, 69.65 GB (2.32 GB used)

Volume V: - Logical, NTFS Compressed, Video Archive, 400.1 GB (156.21 GB used)

Volume S: - Logical, NTFS Compressed, Data Archive, 300.1 GB (169.63 GB used)

Volume T: - Logical, NTFS Compressed, Shared Access, 77.5 GB (132.02 MB used)

Volume R: - Logical, FAT32, Paging File, 4.9 GB (9.89 MB used)

 

Immediately after assigning volumes V, S, T, and R, which didn't exist by factory default, I used WD's Acronis Alignment Tool to properly align all partitions to the AF drive, since clusters are not physical sectors. As expected, volumes V, S, T, and R were not properly aligned because they were by default based upon traditional sector size.

 

Defraggler didn't seem to have any performance issues defragmenting the first 500 giga-bits, but took a significant hit when defragmenting Volume S. By comparison, the high CPU usage and I/O bottleneck seemed to resemble the same problem when running a dynamic VHD on an AF hard drive. Basically, even after running for over 8 hours, Defraggler showed a remaining time of over 1 day. Stopping and restarting Defraggler, with and without rebooting, always showed a remaining time of over 1 day with Volume S, even with less than 20% fragmentation. On the off-chance the bottleneck was related to the display map behavior, I installed the Windows hotfix which updated FSUTIL and storport driver with new queries, function calls, whatever, which allows for 'aligned' writes to the drive. This resolved the bottleneck, and the defragmentation that should have previously taken over one day due to the amount and size of written changes, I'm guessing here, was suddenly reduced to 1 hour and 45 minutes, but completed after approximately 45 minutes.

 

Comparing the latest version of Defraggler on the WDC AF drive, a Seagate GoFlex 2 TB USB 3.0 drive, and 4 Seagate 500 GB 512-byte sector drives in a RAID 10 configuration, the drives using 512-byte emulation exhibited some slight degradation in performance, with only the WD having a dramatic drop in performance after 500 giga-bits. Since the WD is the only AF drive connected directly to the motherboard, and the hidden recovery partition and volumes C and D were properly aligned upon creation or cloning, there could be a physical limitation before the emulation and operating system cannot maintain alignment without the appropriate patch or update. Some USB drives may be exempt from alignment issues because of the external controller. Windows XP requires vendor support for AF drives, but even Windows XP Professional 32-bit has no problem recognizing and defragmenting the Seagate GoFlex 2 TB USB 3.0 hard drive with just the Seagate Dashboard installed. However, only the WD AF drive, which is directly connected to the laptop motherboard exhibits strange behavior with the drive map.

 

As I went through all of the above, I came to realize that the drive map's display "freaks out" only when attempting to defragment the $MFT. If I just click on a block with the $MFT in it, and defragment only that file, or perform various defragmentation methods in Defraggler, the drive map changes only with the $MFT. Interestingly enough, installing the Vista hotfix for AF drives actually changed the strange behavior in the drive map when defragmenting the $MFT. Also by comparision, MyDefrag and the default Windows defragmentation utilities never exhibited any bottlenecks, loss of performance, or in the case of MyDefrag, radical changes to the display map. From what little I can tell, Defraggler is the most recently updated, and might intentionally or unintentionally require the Vista and Windows Server 8 hotfix (http://support.micro....com/kb/2553708) or Windows 7 and Windows Server 2008 R2 update (http://support.microsoft.com/kb/982018) by default to avoid performance loss when defragmenting AF drives. Unfortunately, I still cannot determine if the display map behavior is an actual bug in Defraggler, a possible potential conflict between the logical (512-byte emulation) and physical sectors during defragmentation of the $MFT, or just normal behavior for this version of Defraggler.

 

I've included some screenshots this time (or at least I hope I did).

[eL_PuSHeR]

One minor off-topish advice: Using JPEG for screen captures/snapshots is A VERY BAD IDEA because of its lossy compression. Use PNG instead.

[bmore]

Thanks. I'll remember that for next time. I used the Print Screen key and Paint's default jpeg compression of 75% because I stopped installing software while I was trying to figure out why I was having problems with Defraggler.

 

 

Edit: I just ran Defraggler's benchmark using the original Toshiba 160 GB against the The WD AF 1 TB drive, comparing the cloned partitions. The Toshiba through an eSATA express card showed 25.22 MB/s, but the WD benchmarked with 1.26 MB/s, which doesn't come close to the actual speed of the drive. Once I started Defraggler, and only volumes C, D, and R were displayed, so I had to exit and restart the program for all the volumes to appear. Then today I received an unusual error when trying to defragment using Defraggler, so I again had to exit and restart. Considering everything that I've encountered and read, I'm going to consider the behavior with the display map as Defraggler having a difficult time dealing with AF drives.