Defrag increases "used space" as reported by command-line defrag -

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Why does defrag increase the disk's "used space"? This happens with both the
GUI version, and the command-line version. The command line flag "-w"
results in a greater decrease in used space. I used (command line) defrag c:
-a -v to generate a report, ran the GUI defrag, and then reran a report. It
seems that the GUI version repeatably increases "used space" by about .7 GB.
The "free space" value sometimes doesn't show a decrease, due to the lower
precision of the number (no decimal values), and the amount of fragmentation.
The command line version increased "used space" by 1.37, for each of two
runs that for which I saved the analysis report. The "free space" value IS
reduced for the more aggressive defrag:
"defrag c: -w -v. Is this additional used space usable, or is it lost
forever, or until the disk is reformatted?
 
I have been wondering why there were no replies to my post (my first, ever).
In reading it, I realized A) that the subject doesn't indicate that it is a
question, and B) that I omitted "GB" in the sentence that should have read:
"The command line version increased "used space" by 1.37GB, for each of two
runs for which I saved the analysis report.", and C) the post almost reads as
though it is an answer to something, but I was only trying to give detail on
how I found the problem.

I tried to ask Microsoft, but the webpage says to contact the OEM if Vista
was preinstalled. The response from the OEM didn't address the "problem". Can
anyone help?

Thanks, Mike
 
I have been wondering why there were no replies to my post (my first,
ever).
In reading it, I realized A) that the subject doesn't indicate that it is
a
question, and B) that I omitted "GB" in the sentence that should have
read:
"The command line version increased "used space" by 1.37GB, for each of
two
runs for which I saved the analysis report.", and C) the post almost reads
as
though it is an answer to something, but I was only trying to give detail
on
how I found the problem.

I tried to ask Microsoft, but the webpage says to contact the OEM if Vista
was preinstalled. The response from the OEM didn't address the "problem".
Can
anyone help?
Click to expand...

I think it's more because no one knows the answer or has seen this issue
before. This is a peer to peer user group, and Vista is a new OS.
 
OK, thanks. I'll keep monitoring.

Rock said:
I think it's more because no one knows the answer or has seen this issue
before. This is a peer to peer user group, and Vista is a new OS.
Click to expand...
 
"(e-mail address removed)_SPAM" wrote
OK, thanks. I'll keep monitoring.
Click to expand...

Another person recently posted this same issue in the vista.general
newsgroup. So now there are two of you who have seen this. Maybe it occurs
across the board, but you are the only ones who have seen it and posted
about it. I haven't seen any replies to his post yet.
 
Rock said:
"(e-mail address removed)_SPAM" wrote
Click to expand...
Another person recently posted this same issue in the vista.general
newsgroup. So now there are two of you who have seen this. Maybe it
occurs across the board, but you are the only ones who have seen it and
posted about it. I haven't seen any replies to his post yet.
Click to expand...

I have seen it too, using a simple "degfrag c:" in the command prompt (i.e.,
no switches in the command). I have wondered about it as well and was hoping
your question would get an answer.

Besides this being a new OS, I'm guessing that 97 percent of users simply
use the GUI defrag, not the command-line defrag. I use the the command line
since I have two disks in three partitions for a total of about 175gb. It
takes a LONG time to defrag all of that.
Also, I'm being overly cautious and maybe I shouldnt be. But I'm a little
wary of having Vista defrag an XP drive (I dual boot), so I avoid doing that
by using the command-line method.
Since the command-line method involves using the right-click "run as
administrator," that makes the method fairly well hidden to most users.
Hence my estimate that only 3 percent of us use it.
I'll keep monitoring as well.
 
that would only be successful if you disabled the built in Scheduled Task for defrag run.
if you have not disabled it, the it is defragging the xp partition as well.



(e-mail address removed)




Rock said:
"(e-mail address removed)_SPAM" wrote
Click to expand...
Another person recently posted this same issue in the vista.general
newsgroup. So now there are two of you who have seen this. Maybe it
occurs across the board, but you are the only ones who have seen it and
posted about it. I haven't seen any replies to his post yet.
Click to expand...

I have seen it too, using a simple "degfrag c:" in the command prompt (i.e.,
no switches in the command). I have wondered about it as well and was hoping
your question would get an answer.

Besides this being a new OS, I'm guessing that 97 percent of users simply
use the GUI defrag, not the command-line defrag. I use the the command line
since I have two disks in three partitions for a total of about 175gb. It
takes a LONG time to defrag all of that.
Also, I'm being overly cautious and maybe I shouldnt be. But I'm a little
wary of having Vista defrag an XP drive (I dual boot), so I avoid doing that
by using the command-line method.
Since the command-line method involves using the right-click "run as
administrator," that makes the method fairly well hidden to most users.
Hence my estimate that only 3 percent of us use it.
I'll keep monitoring as well.
 
I see similar things here (Vista Ultimate, all NTFS). I'm pretty sure it
doesn't happen all the time, just sometimes. For instance, I just did a
"defrag -c -w -v" from the command line to see if I could reproduce this
(I've included the report after these comments). Used Space on the C: drive
increased from 13.35GB to 13.65GB and Free Space decreased from 6.18GB to
5.88GB. On the D: drive, Used Space increased from 71.43GB to 73.48GB and
Free Space decreased from 58.09GB to 56.04GB. In both cases, this is the
opposite of what I'd expect from defragmenting the drives. My guess is that
defrag is padding some of the newly defragmented files with free space so
future increases in file size can be handled without going through a space
allocation process. Again, that's purely a guess.

C:\Windows\system32>defrag -c -w -v
Windows Disk Defragmenter
Copyright (c) 2006 Microsoft Corp.

Defragmentation report for volume C: Vista

Volume size = 19.53 GB
Cluster size = 4 KB
Used space = 13.35 GB
Free space = 6.18 GB
Percent free space = 31 %

File fragmentation
Percent file fragmentation = 0 %
Total movable files = 68,794
Average file size = 224 KB
Total fragmented files = 262
Total excess fragments = 477
Average fragments per file = 1.00
Total unmovable files = 56

Free space fragmentation
Free space = 6.18 GB
Total free space extent = 7,080
Average free space per extent = 915 KB
Largest free space extent = 4.39 GB

Folder fragmentation
Total folders = 9,761
Fragmented folders = 2
Excess folder fragments = 6

Master File Table (MFT) fragmentation
Total MFT size = 73 MB
MFT record count = 68,929
Percent MFT in use = 92
Total MFT fragments = 3

Note: On NTFS volumes, file fragments larger than 64MB are not included
in the fragmentation statistics

Defragmentation report for volume C: Vista

Volume size = 19.53 GB
Cluster size = 4 KB
Used space = 13.65 GB
Free space = 5.88 GB
Percent free space = 30 %

File fragmentation
Percent file fragmentation = 0 %
Total movable files = 68,794
Average file size = 224 KB
Total fragmented files = 0
Total excess fragments = 0
Average fragments per file = 1.00
Total unmovable files = 56

Free space fragmentation
Free space = 5.88 GB
Total free space extent = 7,694
Average free space per extent = 802 KB
Largest free space extent = 4.39 GB

Folder fragmentation
Total folders = 9,761
Fragmented folders = 1
Excess folder fragments = 0

Master File Table (MFT) fragmentation
Total MFT size = 73 MB
MFT record count = 68,929
Percent MFT in use = 92
Total MFT fragments = 3

Note: On NTFS volumes, file fragments larger than 64MB are not included
in the fragmentation statistics

Defragmentation report for volume D: My Stuff

Volume size = 130 GB
Cluster size = 4 KB
Used space = 71.43 GB
Free space = 58.09 GB
Percent free space = 44 %

File fragmentation
Percent file fragmentation = 0 %
Total movable files = 58,535
Average file size = 1 MB
Total fragmented files = 22
Total excess fragments = 708
Average fragments per file = 1.01
Total unmovable files = 10

Free space fragmentation
Free space = 58.09 GB
Total free space extent = 15,589
Average free space per extent = 4 MB
Largest free space extent = 19.03 GB

Folder fragmentation
Total folders = 6,461
Fragmented folders = 1
Excess folder fragments = 2

Master File Table (MFT) fragmentation
Total MFT size = 65 MB
MFT record count = 58,827
Percent MFT in use = 88
Total MFT fragments = 3

Note: On NTFS volumes, file fragments larger than 64MB are not included
in the fragmentation statistics

Defragmentation report for volume D: My Stuff

Volume size = 130 GB
Cluster size = 4 KB
Used space = 73.48 GB
Free space = 56.04 GB
Percent free space = 43 %

File fragmentation
Percent file fragmentation = 0 %
Total movable files = 58,535
Average file size = 1 MB
Total fragmented files = 0
Total excess fragments = 0
Average fragments per file = 1.00
Total unmovable files = 10

Free space fragmentation
Free space = 56.04 GB
Total free space extent = 16,302
Average free space per extent = 4 MB
Largest free space extent = 19.03 GB

Folder fragmentation
Total folders = 6,461
Fragmented folders = 1
Excess folder fragments = 0

Master File Table (MFT) fragmentation
Total MFT size = 65 MB
MFT record count = 58,827
Percent MFT in use = 88
Total MFT fragments = 3

Note: On NTFS volumes, file fragments larger than 64MB are not included
in the fragmentation statistics




"(e-mail address removed)_SPAM"
 
"(e-mail address removed)_SPAM"
Why does defrag increase the disk's "used space"? This happens with both
the
GUI version, and the command-line version. The command line flag "-w"
results in a greater decrease in used space. I used (command line) defrag
c:
-a -v to generate a report, ran the GUI defrag, and then reran a report.
It
seems that the GUI version repeatably increases "used space" by about .7
GB.
The "free space" value sometimes doesn't show a decrease, due to the lower
precision of the number (no decimal values), and the amount of
fragmentation.
The command line version increased "used space" by 1.37, for each of two
runs that for which I saved the analysis report. The "free space" value
IS
reduced for the more aggressive defrag:
"defrag c: -w -v. Is this additional used space usable, or is it lost
forever, or until the disk is reformatted?
Click to expand...




See
http://blogs.technet.com/filecab/ar...s-cover-why-windows-vista-defrag-is-cool.aspx

The blog says that defrag attempts to prevent copy-on-write by the Volume
Shadow copy Service (VSS) where possible.
Whenever this is not possible to prevent, VSS's diff space will increase,
decreasing available free space.

The space is not lost forever, it is being used to back up your files that
have "changed" according to VSS, due to their being moved around by defrag.
vssadmin.exe will tell you about your shadow storage space. There is a
default maximum allowed shadow storage space (15% of volume), so you needn't
fear your free space decreasing until there's none left.


-Victoria
 
See
http://blogs.technet.com/filecab/ar...s-cover-why-windows-vista-defrag-is-cool.aspx

The blog says that defrag attempts to prevent copy-on-write by the Volume
Shadow copy Service (VSS) where possible.
Whenever this is not possible to prevent, VSS's diff space will increase,
decreasing available free space.

The space is not lost forever, it is being used to back up your files that
have "changed" according to VSS, due to their being moved around by
defrag.
vssadmin.exe will tell you about your shadow storage space. There is a
default maximum allowed shadow storage space (15% of volume), so you
needn't fear your free space decreasing until there's none left.
Click to expand...

Thanks for the explanation, Victoria.
 
Victoria, I echo Rock's thanks. It is a relief to know that the growth is
limited. I looked at your reference, followed some of the links, and
concluded that the additional space is used for a restore-point in case data
are damaged in the move. Also, thanks for the awareness of other sources of
info. provided by links in the referenced blog. Thanks to everyone who
replied, too.

Mike
 
Sorry, "what" would only be successful?

that would only be successful if you disabled the built in Scheduled Task for defrag run.
if you have not disabled it, the it is defragging the xp partition as well.



(e-mail address removed)




Rock said:
"(e-mail address removed)_SPAM" wrote
Click to expand...
Another person recently posted this same issue in the vista.general
newsgroup. So now there are two of you who have seen this. Maybe it
occurs across the board, but you are the only ones who have seen it and
posted about it. I haven't seen any replies to his post yet.
Click to expand...

I have seen it too, using a simple "degfrag c:" in the command prompt (i.e.,
no switches in the command). I have wondered about it as well and was hoping
your question would get an answer.

Besides this being a new OS, I'm guessing that 97 percent of users simply
use the GUI defrag, not the command-line defrag. I use the the command line
since I have two disks in three partitions for a total of about 175gb. It
takes a LONG time to defrag all of that.
Also, I'm being overly cautious and maybe I shouldnt be. But I'm a little
wary of having Vista defrag an XP drive (I dual boot), so I avoid doing that
by using the command-line method.
Since the command-line method involves using the right-click "run as
administrator," that makes the method fairly well hidden to most users.
Hence my estimate that only 3 percent of us use it.
I'll keep monitoring as well.
 
manually running defrag to prevent defragging your xp drive/partition.
if you still allow the auto Scheduled Task Defrag to run it will still defrag the xp drive.



(e-mail address removed)



Sorry, "what" would only be successful?

that would only be successful if you disabled the built in Scheduled Task for defrag run.
if you have not disabled it, the it is defragging the xp partition as well.



(e-mail address removed)




Rock said:
"(e-mail address removed)_SPAM" wrote
Click to expand...
Another person recently posted this same issue in the vista.general
newsgroup. So now there are two of you who have seen this. Maybe it
occurs across the board, but you are the only ones who have seen it and
posted about it. I haven't seen any replies to his post yet.
Click to expand...

I have seen it too, using a simple "degfrag c:" in the command prompt (i.e.,
no switches in the command). I have wondered about it as well and was hoping
your question would get an answer.

Besides this being a new OS, I'm guessing that 97 percent of users simply
use the GUI defrag, not the command-line defrag. I use the the command line
since I have two disks in three partitions for a total of about 175gb. It
takes a LONG time to defrag all of that.
Also, I'm being overly cautious and maybe I shouldnt be. But I'm a little
wary of having Vista defrag an XP drive (I dual boot), so I avoid doing that
by using the command-line method.
Since the command-line method involves using the right-click "run as
administrator," that makes the method fairly well hidden to most users.
Hence my estimate that only 3 percent of us use it.
I'll keep monitoring as well.
 
I don't.
Thanks for the tip, tho.

manually running defrag to prevent defragging your xp drive/partition.
if you still allow the auto Scheduled Task Defrag to run it will still defrag the xp drive.



(e-mail address removed)



Sorry, "what" would only be successful?

that would only be successful if you disabled the built in Scheduled Task for defrag run.
if you have not disabled it, the it is defragging the xp partition as well.



(e-mail address removed)




Rock said:
"(e-mail address removed)_SPAM" wrote
Click to expand...
Another person recently posted this same issue in the vista.general
newsgroup. So now there are two of you who have seen this. Maybe it
occurs across the board, but you are the only ones who have seen it and
posted about it. I haven't seen any replies to his post yet.
Click to expand...

I have seen it too, using a simple "degfrag c:" in the command prompt (i.e.,
no switches in the command). I have wondered about it as well and was hoping
your question would get an answer.

Besides this being a new OS, I'm guessing that 97 percent of users simply
use the GUI defrag, not the command-line defrag. I use the the command line
since I have two disks in three partitions for a total of about 175gb. It
takes a LONG time to defrag all of that.
Also, I'm being overly cautious and maybe I shouldnt be. But I'm a little
wary of having Vista defrag an XP drive (I dual boot), so I avoid doing that
by using the command-line method.
Since the command-line method involves using the right-click "run as
administrator," that makes the method fairly well hidden to most users.
Hence my estimate that only 3 percent of us use it.
I'll keep monitoring as well.
 
The simple way to recover this lost space is to turn System Restore off and
on again. By the way, when you turn System Restore on in Vista, it does not
automatically create a Restore Point as with XP. You must create a Restore
Point manually - something Microsoft should fix. I just discovered the same
problem as Mike after running defrag c: -r, then defrag c: -w from the
command prompt. I lost 3.6GB the first defrag and then lost another 1.75GB
the second defrag. After turning System Restore off and on, my free space
went from 16% to 41%. This seems like a bug to me - Microsoft, please fix.

HMT
 
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