Image File Size and Hard Disk useable space

I have my system drive divided into 3 partitions for System, Documents and other compressible data and Media files. One reason for doing so was to reduce the System image file to something under 20 GB.

I am using Vista and a 320 GB drive. Partitions are as fol, using Windows Properties function:

---------------------
System 247 GB (this will be reduced as necessary after I know what size I really need)

Documents/Data - 10 GB

Media (Pictures and Videos) - 40.7 GB

Total in Partitions is approx 298 GB
--------------------------

The image size for the Data and Media partitions seemed reasonable. But the System partition image size seems way off.

Here is the breakout of the various component sizes for the System partition (Note that System files and Hidden files were all shown):

Partition size - 247 GB

USED space(from Windows Properties) - 41.5 GB

FREE space - 205.5 GB

Image size (standard compression) - 47.7 GB

Independent check of USED space using DiskPiePro utility - 18.7 GB

Checking individual System partition folders with 'Properties' : approx 15 GB

Trash was empty and Win Clean Disk run before all of this.

I can see that if I add the 'missing' 20 GB (320 - 300) to the approximate 20GB size of the files I count in the System partition, I get about 40 GB, which is about what my system says is the total USED amount in the System partition.

Questions:

On a 320 GB drive, the total space shown by Windows Properties in the 3 partitions is around 300 GB. Where is the other 20 GB?

If the Used space on the System partition for the image was 41.4 GB why was the the image size - using standard compression -47.7 GB?


Charlie

 

Why a 320 Gb drive shows in Windows as 300 Gb, is just the way makers define the amount of space a drive has. Naturally they want it to seem as large as possible. All makers do this. The space Windows shows is usually 6% less.

 

That's interesting.

The box the drive came in actually says "300GB." Then another sticker on the box says "BONUS 20GB. 320GB total capacity inside."

Charlie

 

If it was a standard 300Gb, windows would show it as around 285Gb. All three of my 160Gb (3 different makers) show as 149Gb in windows.

 

Now that I look at it more carefully, I can see why there is a difference.

My "250 GB" drive (1 single partition) shows up in Windows Properties as 249,999,126,528 bytes (249.999 billion bytes) and 232 "GB". That I can understand since the former number uses 1000 as a "k" and the later uses 1024 as a "K". This results in a "GB" being 1,073,741,824 bytes. Divide 250 by 1.073741824 and you get 232, which is the size in GB that is shown in the Properties box for that drive. OK.

My "320 GB" drive shows (adding up the three partitions) in Properties as 320,070,217,728 bytes and 297.7 GB - same math. OK
============================
WRT my other questions:

I understand that there must be space on the disk for housekeeping functions the size of which would not be included in an OS "Properties" function. But that 'unaccounted ' for space cannot be GBs in size.

My system partition space is reported as 41.5 GB Used of 247 GB total. But the Folders and files add up to around 20GB. And the image of that partition is 47.7 GB. So, why is the "Used" space on my system partition 20 GB larger than the total space taken up by the file structure ( Hidden and System files included)? The image obviously included the 'extra' 20 GB in the image. So, they are not phantom bytes...

And, why was the ("Normal") compressed image size for the system partition 15% larger than the "Used" space on the partition? I know there is overhead in the imaging process, so given no compression, I would expect the image to be larger than the target data. But, I would think system files are reasonably compressible and the image would be smaller.


Charlie

 

BTW, I have the same problem with my other internal drive.

It shows in Properties as 232 GB total, 193 GB Used. Adding up the files and folders (Hidden and System files shown) abd adding in a few GB for misc, I count no more than about 140 GB.

Where is the other 53 GB?

Charlie

 

Charlie,

Check the size of your System Volume Information folder. I'll bet you'll find it's huge.

 

Brian,

Explorer tells me there are 0 bytes there. But, running CMD as Administrator and issuing: <vssadmin list shadowstorage> command, give me the fol:

C:\
29.3GB USED / 31 GB ALLOCATED / 44.7 GB MAXIMUM

D:\
0 USED / 0 ALLOCATED / 24.1 MAXIMUM

I should have mentioned in the previous post that D:\ is actually a test image of an earlier single partition version of my current C: drive.

I had been set up for the Default 15% of C:\ drive for System Restore space.
I changed that (with help from "Windows Vista InsideOut" text) in the registry to 2% (Vista no longer allows direct access to this variable via pop-up as XP did). With the 300 GB drive, that should be around 6GB - plenty for the way I use System Restore.

I also changed the length of time Restore files are kept before the system deletes them from the default 90 days to 10 days (again, in the Registry). I figured those two changes should be reflected in the shadowstorage variable. I did a Restart and <vssadmin list shadowstorage> again and I get the same values for disk space for both drives.

So, this does appear to be at least part of my missing storage. Good Call!

But, it looks like I'm going to have to figure out why the Registry changes are not working before I can do anything about it.

Thanks,
Charlie

 

Charlie,

A poster in the TeraByte forum noticed his Vista C: drive used space increase from 18 to 35 GB over a two day period. It was due to System Restore files. As you know, I'm still with WinXP so I can't test this. Glad you got it sorted out.

One of his posts...

Have you tried TreeSize? It lets you find those aberrant big folders easily. A great app.

http://www.jam-software.com/freeware/index.shtml

 

Charlie:

Run Disk Cleanup on Vista and choose "Files from all users on this computer". After selecting the C: drive, let it find things that can be deleted. Choose the "More Options" tab and under "System Restore and Shadow Copies", choose to delete all but the most recent restore point. This should clean out your shadow copies and then Vista will then probably honor the maximum 6 GB limit that you have set in the registry.

The vssadmin command will also let you resize the amount of space that Vista reserves for system restore and shadow copy files. From an elevated command prompt type:

Code:

vssadmin /?

to get a list of available commands, then :

Code:

vssadmin Resize ShadowStorage /?

to get a description of the resize command.

 

Brian,
Now that I have been more attentive to the USED value, I also can see a steady increase in USED size for my C:\ drive. It has increased about 2 GB in one day!

I have been using a graphical version of this type of app - DiskPiePro - but TreeSize is quicker and more useful.

Thanks!!

Charlie

 

Worked like a champ!! Knocked off over 20GB and now my C:\ drive shows only 18.1GB used, which is about what I had determined it should be.

Also, your vssadmin command info was very helpful to me in getting this sorted out.

Saved my first System Restore point, afterwards and determined it used 8MB in the ShadowStorage area on C:

Thanks, again for everyone's help in this...
Charlie

 

Charlie:

Great! Glad to hear that this worked for you.

Another thing to watch out for on Vista is that the system restore function and the Previous Versions of Files (Shadow Copies) that are saved by Vista are operating at the sector level on the disk. Anything that rearranges the sectors, like a disk defragmenter, will cause the shadow copy file size to grow dramatically. If you note the size of the files with "vssadmin List ShadowStorage" and then you defragment your disk, you will see a large increase in the size of the files at the time your next restore point is created. Again, that's because the new restore point will treat any sectors that have changed, including the ones that were just moved around, as filesystem updates that need to be stored.

You can deal with this manually by doing another disk cleanup and deleting all but the most recent restore point just after defragmenting your disk. Or, if you rely on the shadow copy files as part of your backup scheme, you can substantially restrict the growth of the shadow copy files by changing the cluster size on the NTFS partitions where System Restore is enabled from the default 4 kB to 16 kB.

I personally rely on shadow copy files as part of my backup scheme and have found that I can get about 30 days of shadow copies to fit in 3 GB, even after weekly defragmenting, with a 16 kB cluster size. Before, with 4 kB clusters, I'd fill up the 6 GB that I have reserved for shadow copies in only 3 weeks.

More here on the Acronis Disk Director forum if you're interested.

 

k0lo,
This is very helpful info for me. Thanks for your assistance.

Charlie