Defrag - Vista vs. XP

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Out of curiosity, I ran the Vista Defrag utility on my XP hard drive [system
has 2 SATA drives, one with XP, the other with Vista RC2]. I figured that as
no files were open on the XP drive I would get a more complete defrag.

So, from the command prompt "defrag e: -v"; wait a while; report on
fragmentation; lots of disk activity; another report on fragmentation;
command prompt. Oddly, the two fragmentation reports seemed to be identical -
I assumed that this must be a bug, so I ran defrag again. The inital report
on the second run was very differerent from the final report on the first
run, so my assumption seems reasonable, and the first run really had made
significant changes. The second run also produced similar reports, so I ran
defrag a third time (analysis only). The only significant difference between
the two results was that the number of free space fragments had increased
[this supports my belief that MS does not understand the need to defragment
free space].

As it was difficult to build a picture of what was really going on on the
disk, I decided to reboot XP and look at the pretty pictures. The XP Disk
Defragmenter analyze display showed an awful lot of red, with a mix of small
and large files reported as fragmented. So I ran one defrag pass, with a
result of no file fragmentation at all.

This raises a number of issues, some I have seen brought up before:

1. The lack of a graphical analysis display in Vista is a problem. It really
is much easier to glance at a picture and understand what is going on.

2. The Vista command line defrag verbose report does not include individual
file information (as the XP analysis report does). This further hampers your
ability to understand what is going on.

3. The XP defrag cleaned up a mess left by the Vista defrag - shouldn't this
be the other way around?

4. Why is the free space not defragmented? Given the current scheme when you
load up one massive video file it is automatically broken up into thousands
of small pieces.

I think that basing the Vista defrag on the 64MB unit would make more sense.
I don't mind a big file being broken up into 64MB chunks, and I'd like all
the little files jammed into 64MB chunks also, so that the free space would
consist of lots of 64MB chunks (some contiguous, some not), with very few
pieces of free space smaller than 64MB. Then when I load a large video file I
may not need to clean up at all...
 
I had similiar issues with the Vista Defrag so I installed the Diskeeper
software for Vista. Now I get all the graphic display back as well as defrag
of free space. TTFN.
 
Hi Dave,

Given the information in the post it is difficult to say difinitively what
is going on. If you believe that you have run into a bug with the pre and
post defragmentation reports from the command line, please submit a bug with
detailed information (at least the verbose reports after each step) and we
will try to reproduce this and understand what is going on. It would also be
helpful to specify what kinf of files you had on the volume. If there was a
large number of files larger than 64 MB it is conceivable that you could see
very different fragmentation statistics from Vista nad XP but we'll need to
confirm that this is the case.

In your post you also mention free space fragmentation. Let me assure you
that we do indeed understand the problem of free space fragmentation and the
Vista defragmenter performs free space consolidation. That said, it does not
just blindly try to compact everything as much as possible since this would
take forever, but tries to be a bit more intelligent and make sure that the
largest free space extent grows. This will help address the scenarios of
copying a large video that you describe. We also try to minimize the number
of moves since excessive changes will lead to quickly exhausting the
snapshot diff area for the given volume and you will start losing previous
versions (if enabled) as a result of defragmentation.

Thank you again for participating in the Windows Vista beta program.

Georgi Matev [MSFT]
PM Clusters, File Systems, and Storage

This posting is provided "AS IS" with no warranties, and confers no rights.

Dave Nuttall said:
Out of curiosity, I ran the Vista Defrag utility on my XP hard drive
[system
has 2 SATA drives, one with XP, the other with Vista RC2]. I figured that
as
no files were open on the XP drive I would get a more complete defrag.

So, from the command prompt "defrag e: -v"; wait a while; report on
fragmentation; lots of disk activity; another report on fragmentation;
command prompt. Oddly, the two fragmentation reports seemed to be
identical -
I assumed that this must be a bug, so I ran defrag again. The inital
report
on the second run was very differerent from the final report on the first
run, so my assumption seems reasonable, and the first run really had made
significant changes. The second run also produced similar reports, so I
ran
defrag a third time (analysis only). The only significant difference
between
the two results was that the number of free space fragments had increased
[this supports my belief that MS does not understand the need to
defragment
free space].

As it was difficult to build a picture of what was really going on on the
disk, I decided to reboot XP and look at the pretty pictures. The XP Disk
Defragmenter analyze display showed an awful lot of red, with a mix of
small
and large files reported as fragmented. So I ran one defrag pass, with a
result of no file fragmentation at all.

This raises a number of issues, some I have seen brought up before:

1. The lack of a graphical analysis display in Vista is a problem. It
really
is much easier to glance at a picture and understand what is going on.

2. The Vista command line defrag verbose report does not include
individual
file information (as the XP analysis report does). This further hampers
your
ability to understand what is going on.

3. The XP defrag cleaned up a mess left by the Vista defrag - shouldn't
this
be the other way around?

4. Why is the free space not defragmented? Given the current scheme when
you
load up one massive video file it is automatically broken up into
thousands
of small pieces.

I think that basing the Vista defrag on the 64MB unit would make more
sense.
I don't mind a big file being broken up into 64MB chunks, and I'd like all
the little files jammed into 64MB chunks also, so that the free space
would
consist of lots of 64MB chunks (some contiguous, some not), with very few
pieces of free space smaller than 64MB. Then when I load a large video
file I
may not need to clean up at all...
Click to expand...
 
Hi Georgi,

I'm running under XP right now. I'll make a mess on the disk and repeat the
experiment later today. I'll capture the command line verbose reports, and
the XP reports. Assuming that I get similar results, how should I report them?

Best regards,

Dave
 
Thanks Jill.

I've tried several times to re-create the issue where the same report shows
up at the start and end of "defrag e: -v" when defragmentation had happened,
but I can't. I guess that I must have misread the reports as being the same...
 
In your post you also mention free space fragmentation. Let me assure you
that we do indeed understand the problem of free space fragmentation and the
Vista defragmenter performs free space consolidation. That said, it does not
just blindly try to compact everything as much as possible since this would
take forever, but tries to be a bit more intelligent and make sure that the
largest free space extent grows. This will help address the scenarios of
copying a large video that you describe. We also try to minimize the number
of moves since excessive changes will lead to quickly exhausting the
snapshot diff area for the given volume and you will start losing previous
versions (if enabled) as a result of defragmentation.
Click to expand...
Here's an example where a video file is copied onto the system (in XP), and
then the disk is defragged in Vista:

XP defrag analysis report:

Fragments File Size Most fragmented files
5,223 508 MB \Temp\Molto Mario\Sagnatielle.mpg

Vista defrag run 1, initial report

File fragmentation
Percent file fragmentation = 0 %
Total movable files = 110,555
Average file size = 1 MB
Total fragmented files = 279
Total excess fragments = 6,118
Average fragments per file = 1.05
Total unmovable files = 23

Free space fragmentation
Free space = 46.77 GB
Total free space extent = 4,155
Average free space per extent = 12 MB
Largest free space extent = 16.76 GB

Vista defrag run 1, final report

File fragmentation
Percent file fragmentation = 0 %
Total movable files = 110,555
Average file size = 1 MB
Total fragmented files = 1
Total excess fragments = 1
Average fragments per file = 1.00
Total unmovable files = 23

Free space fragmentation
Free space = 46.77 GB
Total free space extent = 10,014
Average free space per extent = 5 MB
Largest free space extent = 16.88 GB

Vista defrag run 2, final report

Free space fragmentation
Free space = 46.77 GB
Total free space extent = 8,748
Average free space per extent = 5 MB
Largest free space extent = 18.94 GB

Vista defrag run 3, final report

Free space fragmentation
Free space = 46.77 GB
Total free space extent = 8,692
Average free space per extent = 6 MB
Largest free space extent = 21.41 GB

I see your point about the largest free space extent growing, but my problem
is that the size of the video file is not known as it is being copied onto
the system - so that it tends to get scattered around all the little pieces
of free space which don't seem to be coming down in number very quickly.
 
tonytwo said:
I dont like the Vista Defragger too, its really slow and aint auto
either. Had too many problems
Click to expand...

What do you mean "aint auto"? By default it's set up to run on at a certain
time - I don't remember how often - at a late hour. That can be changed to
suit your needs. Of course you don't see the fancy GUI - some folks miss
being mesmerized by colored blocks moving around I guess.
 
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