w2k pro/MFT Bitmap

keithy397 · 10-04-2005, 01:56 PM

OK here's the story!

A while back I used a PC performance enhancer tool (on bad recommendation) and afterwards I noticed that when I ran the defrag I had 32% of disk space occupied with system files.

After a lot of checking around I discovered it had changed my paging file size to 1728mb. I changed it back to one and a half times RAM, rebooted etc but the 'occupied' space still showed in the defrag.

Further checks definitely showed that space free.

Finally I ran chkdsk and it reported:-
CHKDSK discovered free space marked as allocated in the master file table (MFT) bitmap.

I know this is to do with the NTFS

but that's it.

Now I have searched around the web for days and can't find a solution so I'm hoping to find one here!

**Resolution** · 10-04-2005, 02:18 PM

Check to see if the filesystem is dirty. From the command prompt, type the following...

fsutil dirty query C:

If it comes up clean, then you don't have to run chkdsk again. If it comes up dirty, then you will have to flag the filesystem as "dirty" by typing fsutil dirty set C:, which will automatically scan the drive for errors on your next reboot.

Now you know why those "performance tools" tell you to use them at your own risk.

keithy397 · 10-04-2005, 04:40 PM

Tried it and it said fsutil is not recognised as an internal or external command

Next?

Stu_computer · 10-04-2005, 05:38 PM

fsutil is a Win XP command, for w2k use Chkntfs C: to check for dirty bit.

Did you use chkdsk C: /f to do a cleanup?

Windows doesn't have a utility to reclaim unused MFT allocated space, there are third-party defraging utilities $$ that can.

**Resolution** · 10-04-2005, 06:02 PM

Quote:

Originally Posted by Stu_computer

fsutil is a Win XP command, for w2k use [

Thanks for the correction.

keithy397 · 10-05-2005, 02:28 AM

Thanks Stu_Computer & Resolution for your input.

Quote:

Originally Posted by Stu_computer

fsutil is a Win XP command, for w2k use Chkntfs C: to check for dirty bit.

I ran the Chkntfs C: command and response was C: is not dirty.

Quote:

Originally Posted by Stu_Computer

Did you use chkdsk C: /f to do a cleanup?

I didn't use chkdsk C: /f, I went via the right click on C: drive icon (in windows), Properties, Tools, Error Checking and then Check Disk which then stated it would chkdsk on reboot which is what it did.

Quote:

Originally Posted by Stu_Computer

Windows doesn't have a utility to reclaim unused MFT allocated space, there are third-party defraging utilities $$ that can.

Sort of guessed this wasn't going to be easy!!

Thanks so far, what's next then?

**Resolution** · 10-05-2005, 02:46 AM

After doing a little searching, it seems like there might be a registry tweak for this.

Open your registry and go to the following key...

HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\FileSystem

Look for a value that says NtfsMftZoneReservation. If it is not there, then add it and set the DWORD value to 1, which is the default value. Now, close the registry and reboot your system. Check to see if there was any space change.

Stu_computer · 10-06-2005, 04:42 PM

NtfsMftZoneReservation is used to allocate a default zone size for new partitions, shouldn't mess with it if you don't know about MFT.

If it's presenting a problem and you need to keep the current windows installation you can buy diskeeper to shrink MFT. (I've never used it)

Alternatively, if it's not a big issue then continue to use as is and when it becomes necessary the MFT space will be automatically reallocated for new files.

For future reference, if you use software that has tonnes of files (games are a good example) then it's best to put it in another partition since every NTFS partition gets it's own MFT and it's a simple matter of reformating the partition (or repartitioning/formatting as needed). It's also more efficient since the MFT will keep small files (1.5k or less) within the zone which means faster access.

keithy397 · 10-29-2005, 02:36 AM

Sorry for the delay guys, in between looking up on this I had other things on my plate.

The easy answer is it's sorted now! With a combination of great advice from Resolution and Stu_Computer and an element of good fortune I hit the jackpot!

I did quite a bit of research on this (and took good advice) and discovered that the MFT file will increase in size as you add more and more files to your PC but you can't reduce it's size by any 'normal everyday' procedure. It can only be done with a 3rd party defragger (as Stu_Computer mentioned), so I d/l PerfectDisk, set it for a boot MFT defrag, rebooted, let it do it's thing and voila!! the MFT allocation was greatly reduced.

Thanks very much for your advice guys, couldn't have done it without you pointing me in the right direction.

10-04-2005, 01:56 PM	#1 (permalink)
keithy397 Alternative Computing Team Join Date: Jul 2004 Location: Anglesey, North Wales Posts: 486 OS: w2k pro	w2k pro/MFT Bitmap OK here's the story! A while back I used a PC performance enhancer tool (on bad recommendation) and afterwards I noticed that when I ran the defrag I had 32% of disk space occupied with system files. After a lot of checking around I discovered it had changed my paging file size to 1728mb. I changed it back to one and a half times RAM, rebooted etc but the 'occupied' space still showed in the defrag. Further checks definitely showed that space free. Finally I ran chkdsk and it reported:- *CHKDSK discovered free space marked as allocated in the master file table (MFT) bitmap.* I know this is to do with the NTFS but that's it. Now I have searched around the web for days and can't find a solution so I'm hoping to find one here! __________________ Cheers, Remember to clear Firefox cache regularly Tools > Options > Advanced > Network > Offline Storage > Clear Now

10-04-2005, 02:18 PM	#2 (permalink)
Resolution TSF Enthusiast Join Date: Sep 2005 Location: Louisiana Posts: 1,091 OS: FreeBSD/Win98/2000/XP	Check to see if the filesystem is dirty. From the command prompt, type the following... fsutil dirty query C: If it comes up clean, then you don't have to run chkdsk again. If it comes up dirty, then you will have to flag the filesystem as "dirty" by typing fsutil dirty set C:, which will automatically scan the drive for errors on your next reboot. Now you know why those "performance tools" tell you to use them at your own risk. Last edited by Resolution; 10-04-2005 at 02:20 PM.

10-04-2005, 04:40 PM	#3 (permalink)
keithy397 Alternative Computing Team Join Date: Jul 2004 Location: Anglesey, North Wales Posts: 486 OS: w2k pro	Tried it and it said fsutil is not recognised as an internal or external command Next? __________________ Cheers, Remember to clear Firefox cache regularly Tools > Options > Advanced > Network > Offline Storage > Clear Now

10-06-2005, 04:42 PM	#8 (permalink)
Stu_computer Tech Hardware Team Join Date: Jul 2005 Posts: 1,461 OS: Windows	NtfsMftZoneReservation is used to allocate a default zone size for new partitions, shouldn't mess with it if you don't know about MFT. If it's presenting a problem and you need to keep the current windows installation you can buy diskeeper to shrink MFT. (I've never used it) Alternatively, if it's not a big issue then continue to use as is and when it becomes necessary the MFT space will be automatically reallocated for new files. For future reference, if you use software that has tonnes of files (games are a good example) then it's best to put it in another partition since every NTFS partition gets it's own MFT and it's a simple matter of reformating the partition (or repartitioning/formatting as needed). It's also more efficient since the MFT will keep small files (1.5k or less) within the zone which means faster access. __________________

10-29-2005, 02:36 AM	#9 (permalink)
keithy397 Alternative Computing Team Join Date: Jul 2004 Location: Anglesey, North Wales Posts: 486 OS: w2k pro	Sorry for the delay guys, in between looking up on this I had other things on my plate. The easy answer is it's sorted now! With a combination of great advice from Resolution and Stu_Computer and an element of good fortune I hit the jackpot! I did quite a bit of research on this (and took good advice) and discovered that the MFT file will increase in size as you add more and more files to your PC but you can't reduce it's size by any 'normal everyday' procedure. It can only be done with a 3rd party defragger (as Stu_Computer mentioned), so I d/l PerfectDisk, set it for a boot MFT defrag, rebooted, let it do it's thing and voila!! the MFT allocation was greatly reduced. Thanks very much for your advice guys, couldn't have done it without you pointing me in the right direction. __________________ Cheers, Remember to clear Firefox cache regularly Tools > Options > Advanced > Network > Offline Storage > Clear Now

10-04-2005, 05:38 PM	#4 (permalink)
Stu_computer Tech Hardware Team Join Date: Jul 2005 Posts: 1,461 OS: Windows	fsutil is a Win XP command, for w2k use Chkntfs C: to check for dirty bit. Did you use chkdsk C: /f to do a cleanup? Windows doesn't have a utility to reclaim unused MFT allocated space, there are third-party defraging utilities $$ that can.

10-05-2005, 02:46 AM	#7 (permalink)
Resolution TSF Enthusiast Join Date: Sep 2005 Location: Louisiana Posts: 1,091 OS: FreeBSD/Win98/2000/XP	After doing a little searching, it seems like there might be a registry tweak for this. Open your registry and go to the following key... HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\FileSystem Look for a value that says NtfsMftZoneReservation. If it is not there, then add it and set the DWORD value to 1, which is the default value. Now, close the registry and reboot your system. Check to see if there was any space change.