Windows directory: $hf_mig$

Bullwinkle · External Since: Oct 15, 2006 Posts: 52

I'm running windows xp sp2 an looking in the c:\windows directory, the first
sub directory is the on above $hf_mig$.

In looking at the contents of this directory I see all the windows updates
in sub-directories.

Do I need to keep these files? Or can I delete them without causing problems
in running windows?

Any help appreciated

Regards,

Patti MacLeod · External Since: Apr 22, 2006 Posts: 549

Hi Bullwinkle,

You should keep those files. Have a look here for a description of the
function of that folder:

Description of the contents of Windows XP Service Pack 2 and Windows Server
2003 software update packages
http://support.microsoft.com/default.aspx?scid=824994
Scroll down to the "Notes" section

Regards,

--
Patti MacLeod
Microsoft MVP - Windows Shell/User

"Bullwinkle" wrote:

> I'm running windows xp sp2 an looking in the c:\windows directory, the first
> sub directory is the on above $hf_mig$.
>
> In looking at the contents of this directory I see all the windows updates
> in sub-directories.
>
> Do I need to keep these files? Or can I delete them without causing problems
> in running windows?
>
> Any help appreciated
>
> Regards,
>
>
>

"cquirke · External Since: Mar 06, 2005 Posts: 825

On Tue, 10 Jul 2007 07:22:01 -0700, Patti MacLeod

>You should keep those files. Have a look here for a description of the
>function of that folder:
>
>Description of the contents of Windows XP Service Pack 2 and Windows Server
>2003 software update packages
>http://support.microsoft.com/default.aspx?scid=824994
>Scroll down to the "Notes" section

You can keep them, but not have them clogging up C:, if you have a
small C: volume that is intended to operate as a lean, fast "engine
room". As it is, for every 1 active code file, you can end up with 3
inactive forms of the same file (DLL cache, patch backup version,
patch new vserion). I can't see a 75% dead-weight overhead tolerated
anywhere else (75% RAM unused, 75% CPU cycles unused), can you?

That way, if you need to "undo" a patch, you can copy the material
back to C: before doing so.

If you follow this approach, you can free about 600M to over 1G on C:,
just by moving off the main $hf_mig$ subtree and the other $..$
subtrees that follow it.

That's before you look at "harder" bloat targets, like Installer,
ServicePackFiles, Downloaded Installations and SoftwareDistribution.
Of those, I generally only relocate ServicePackFiles.

However, if you do relocate these, it's important to keep layering the
relocated set with new stuff as it is spawned by updates etc. else the
subtree will no longer be complete and accurate.

>------------------------- ---- --- -- - - - -
I'm on a ten-year lunch break
>------------------------- ---- --- -- - - - -

Bullwinkle · External Since: Oct 15, 2006 Posts: 52

Thank you Patti. I basically just want to know if this is wasted space. I
have plenty of room to keep them there.

Regards,

"Patti MacLeod" <pam120.RemoveThis@nospamshaw.ca> wrote in message
news:6B0E9C26-0C47-4FBF-B40B-F77F90133994@microsoft.com...
> Hi Bullwinkle,
>
> You should keep those files. Have a look here for a description of the
> function of that folder:
>
> Description of the contents of Windows XP Service Pack 2 and Windows
> Server
> 2003 software update packages
> http://support.microsoft.com/default.aspx?scid=824994
> Scroll down to the "Notes" section
>
>
>
> Regards,
>
> --
> Patti MacLeod
> Microsoft MVP - Windows Shell/User
>
>
> "Bullwinkle" wrote:
>
>> I'm running windows xp sp2 an looking in the c:\windows directory, the
>> first
>> sub directory is the on above $hf_mig$.
>>
>> In looking at the contents of this directory I see all the windows
>> updates
>> in sub-directories.
>>
>> Do I need to keep these files? Or can I delete them without causing
>> problems
>> in running windows?
>>
>> Any help appreciated
>>
>> Regards,
>>
>>
>>

Patti MacLeod · External Since: Apr 22, 2006 Posts: 549

You're welcome Smile

Regards,

--
Patti MacLeod
Microsoft MVP - Windows Shell/User

"Bullwinkle" wrote:

> Thank you Patti. I basically just want to know if this is wasted space. I
> have plenty of room to keep them there.
>

Bullwinkle · External Since: Oct 15, 2006 Posts: 52

Thank you for the info.

Regards,

"cquirke (MVP Windows shell/user)" <cquirkenews.DeleteThis@nospam.mvps.org> wrote in
message news:v1a993teblgl0e94stekgoe8i1lncpiura@4ax.com...
> On Tue, 10 Jul 2007 07:22:01 -0700, Patti MacLeod
>
>>You should keep those files. Have a look here for a description of the
>>function of that folder:
>>
>>Description of the contents of Windows XP Service Pack 2 and Windows
>>Server
>>2003 software update packages
>>http://support.microsoft.com/default.aspx?scid=824994
>>Scroll down to the "Notes" section
>
> You can keep them, but not have them clogging up C:, if you have a
> small C: volume that is intended to operate as a lean, fast "engine
> room". As it is, for every 1 active code file, you can end up with 3
> inactive forms of the same file (DLL cache, patch backup version,
> patch new vserion). I can't see a 75% dead-weight overhead tolerated
> anywhere else (75% RAM unused, 75% CPU cycles unused), can you?
>
> That way, if you need to "undo" a patch, you can copy the material
> back to C: before doing so.
>
> If you follow this approach, you can free about 600M to over 1G on C:,
> just by moving off the main $hf_mig$ subtree and the other $..$
> subtrees that follow it.
>
> That's before you look at "harder" bloat targets, like Installer,
> ServicePackFiles, Downloaded Installations and SoftwareDistribution.
> Of those, I generally only relocate ServicePackFiles.
>
> However, if you do relocate these, it's important to keep layering the
> relocated set with new stuff as it is spawned by updates etc. else the
> subtree will no longer be complete and accurate.
>
>
>
>>------------------------- ---- --- -- - - - -
> I'm on a ten-year lunch break
>>------------------------- ---- --- -- - - - -

LadyDungeness · External Since: Jul 13, 2007 Posts: 17

So, If I move the $hf_mig$ subtree & folders to my G drive, will
future updates know to add their folders there? Should I make a
redirect command or regkey someplace? Should I just add new $hf_mig$
subfolders as they accumulate?

Thanks.

`
Lady Dungeness
Crabby, but Delicious!
~~~~~~~~~~~~~~~~~~~~~~

On Wed, 11 Jul 2007 12:01:10 +0200, "cquirke (MVP Windows shell/user)"
<cquirkenews.DeleteThis@nospam.mvps.org> wrote:

|On Tue, 10 Jul 2007 07:22:01 -0700, Patti MacLeod
|
|>You should keep those files. Have a look here for a description of the
|>function of that folder:
|>
|>Description of the contents of Windows XP Service Pack 2 and Windows Server
|>2003 software update packages
|>http://support.microsoft.com/default.aspx?scid=824994
|>Scroll down to the "Notes" section
|
|You can keep them, but not have them clogging up C:, if you have a
|small C: volume that is intended to operate as a lean, fast "engine
|room". As it is, for every 1 active code file, you can end up with 3
|inactive forms of the same file (DLL cache, patch backup version,
|patch new vserion). I can't see a 75% dead-weight overhead tolerated
|anywhere else (75% RAM unused, 75% CPU cycles unused), can you?
|
|That way, if you need to "undo" a patch, you can copy the material
|back to C: before doing so.
|
|If you follow this approach, you can free about 600M to over 1G on C:,
|just by moving off the main $hf_mig$ subtree and the other $..$
|subtrees that follow it.
|
|That's before you look at "harder" bloat targets, like Installer,
|ServicePackFiles, Downloaded Installations and SoftwareDistribution.
|Of those, I generally only relocate ServicePackFiles.
|
|However, if you do relocate these, it's important to keep layering the
|relocated set with new stuff as it is spawned by updates etc. else the
|subtree will no longer be complete and accurate.
|
|
|
|>------------------------- ---- --- -- - - - -
| I'm on a ten-year lunch break
|>------------------------- ---- --- -- - - - -

"cquirke · External Since: Mar 06, 2005 Posts: 825

On Fri, 13 Jul 2007 02:56:56 -0700, LadyDungeness.TakeThisOut@Fish.Net wrote:

>So, If I move the $hf_mig$ subtree & folders to my G drive, will
>future updates know to add their folders there?

No. A new $hf_mig$ will be spawned in %WinDir% again.

>Should I make a redirect command or regkey someplace?

AFAIK it's hard-coded, hence...

http://cquirke.spaces.live.com/blog/cns!C7DAB1E724AB8C23!302.entry

>Should I just add new $hf_mig$
>subfolders as they accumulate?

That's what I've been doing Smile

>--------------- ---- --- -- - - - -
Saws are too hard to use.
Be easier to use!
>--------------- ---- --- -- - - - -

AlterGeek · Joined: Jan 10, 2007 Posts: 2

Uses of the directory are remembered under [HKLM]\Software\Microsoft\Updates, in Location values. However, those appear to be scattered all over, and apply to only some of the files in a particular patch set. For example, SP0\KB931768-IE7\Filelist, 55 through 80 used $hf_mig$, but not the rest.

A scan of all *.ini files under %windir% was no help. There is no mention of $hf_mig$ there. The earlier observation, that $hf_mig$ location is hardcoded, may be correct...

alan_b · Joined: Mar 06, 2009 Posts: 1

Answer :- Folder Junctions ! ! !

I have relocated 2 GB of "bloat" from C: to S: - no problems encountered.

S:\C_Static\I386 now holds what sat in C:\I386
plus a text file named "Used_At.txt" which states
"These files are now at S:\C_Static\I386. They were at C:\I386. New Folder Junction C:\I386 now aims at this directory."

I deleted C:\I386 with all its contents,
and replaced it with a Folder Junction that designates S:\C_Static\I386.

Comparing C:\*.* before and after shows no difference other than what appears to be a new file C:\I386\Used_At.txt

Similar tricks work with
S:\C_Static\ServicePackFiles
S:\C_Static\My Music

The only peculiarity is that S:\C_Static\My Music\desktop.ini causes Windows Explorer tree view to rename the folder as "C:\C_static\Shared Music"
and also to use a music note icon folder whilst
C:\Documents and Settings\All Users\Documents\Shared Music now has a standard folder icon without the music note - I am happy to live with that.

If I ever forget where I relocated these things, I only have to search for the files "Used_At.txt".

H E L P Am I about to fall over the edge ?
I am about to do the same with C:\Windows\$hf_mig$ but relocating to
D:\Safe\C_Semi_Static\$hf_mig$
Is this safe - or will it unleash a special gotcha,
such as the absence of a music note because C:\...\Shared Music\desktop.ini is not physically present on C: , even though it is fully accessible via the Folder Junction ?

Acronis True Image can tell the difference,
it preserves the Folder Junction but not the contents of S:\
so the backup images are 25% smaller and take 25% less time to create/restore.

I also have a backup image of S:\, but the contents almost never change so this is 2 GB that almost never needs re-imaging.

I use xplorer2 in preference to Windows Explorer, and the discovery that xplorer2 easily creates Folder Junctions was a very pleasant surprise.

I hope the above will help others to trim bloat out of C:\
and would appreciate any warnings of possible danger doing the same to $hf_mig$.

Regards
Alan