NTFS vs FAT32 storage efficiency

B

Bob

I have an older system running Win98se and using FAT32 on
a 120GB drive that I have been using as a file server in
my home. I'm in the process of replacing that system with
a newer one that is running Win2K and has a 250GB drive.

On the new system, I broke the 250GB drive into four equal
partitions of 58.4GB each (after subtracting out the
overhead of the file system) and accepted the default
block size, which I guess was 4096 bytes. I then set up an
overnight network file transfer to copy 54.5GB worth of
files from the old system to the new one.

I was surprised to discover that the 54.5GB of files from
the FAT32 file system would not fit into one of the 58.4GB
partitions of the NTFS file system. I wound up splitting
the files into two of the new partitions for a total of
87.4GB. This is a 60% increase in size !

Well, I was shocked, but realized that it must have been
the 4K block size that was to blame, so I took one of the
remaining, as yet unused, partitions and told Win2K to
reformat it as NTFS using 512 byte blocks. Surely, this
would fix the problem I thought. I then copied the files
from one of the first two partitions (with 4K blocks) into
the reformatted partition with 512 byte blocks). Much to
my surprise, the amount of space required was exactly the
same in both partitions; 54.2GB. I don't understand this
because there are litterally 1000's of files involved and
one would expect to see at least some difference with a
different block size.

I then decided to take the final unused NTFS partition and
reformat it as FAT32 so I could confirm that that was the
only real difference and was responsible for the size
bloat. I tried both a quick format and a full format, but
either way, it tried and then gave up saying "Unable to
complete format." or something very close to that. I know
you can't covert an NTFS file system back to FAT32, but I
thought that I could at least reformat it back if I didn't
care about the contents (of which there were none). So, I
don't understand that either.

Finally, in the research that I've done since, I've noted
several places that say that in WinXP, one can't create a
FAT32 file system larger than 32GB. I don't remember if
that limit also exists for Win2K, but if it does, then
that is probably why I can't reformat those 58.4GB
partitions using FAT32. But, then, I have to wonder why
the OS even gives me that option when it already knows the
size of the partition.

If FAT32 is always limited to a maximum of 32GB, then I
also have to ask how it is that I was able to create a
120GB FAT32 partition under Win98se. Perhaps there was
some magic done by the disk controller on that system that
made this possible. Its been so long since I installed
that drive that I no longer remember the details, but if
that's the case, the perhaps that disk controller magic is
also responsible for the storage efficiency of that system.

I'd be most grateful for any light that anyone can shed on
any of these mysteries.
 
D

Dave Patrick

Inline Reply:

:
<snip>
| If FAT32 is always limited to a maximum of 32GB, then I
| also have to ask how it is that I was able to create a
| 120GB FAT32 partition under Win98se. Perhaps there was
| some magic done by the disk controller on that system that
| made this possible. Its been so long since I installed
| that drive that I no longer remember the details, but if
| that's the case, the perhaps that disk controller magic is
| also responsible for the storage efficiency of that system.
<snip>

* You can use Partition Magic or even Win98 to format a fat32 partition > 32
gB It's simply a limitation of Windows 2000 as far as formatting the
partition.


--
Regards,

Dave Patrick ....Please no email replies - reply in newsgroup.
Microsoft MVP [Windows NT/2000 Operating Systems]
http://www.microsoft.com/protect.
 
L

Leonard Severt [MSFT]

I have an older system running Win98se and using FAT32 on
a 120GB drive that I have been using as a file server in
my home. I'm in the process of replacing that system with
a newer one that is running Win2K and has a 250GB drive.

On the new system, I broke the 250GB drive into four equal
partitions of 58.4GB each (after subtracting out the
overhead of the file system) and accepted the default
block size, which I guess was 4096 bytes. I then set up an
overnight network file transfer to copy 54.5GB worth of
files from the old system to the new one.

I was surprised to discover that the 54.5GB of files from
the FAT32 file system would not fit into one of the 58.4GB
partitions of the NTFS file system. I wound up splitting
the files into two of the new partitions for a total of
87.4GB. This is a 60% increase in size !

Well, I was shocked, but realized that it must have been
the 4K block size that was to blame, so I took one of the
remaining, as yet unused, partitions and told Win2K to
reformat it as NTFS using 512 byte blocks. Surely, this
would fix the problem I thought. I then copied the files
from one of the first two partitions (with 4K blocks) into
the reformatted partition with 512 byte blocks). Much to
my surprise, the amount of space required was exactly the
same in both partitions; 54.2GB. I don't understand this
because there are litterally 1000's of files involved and
one would expect to see at least some difference with a
different block size.

I then decided to take the final unused NTFS partition and
reformat it as FAT32 so I could confirm that that was the
only real difference and was responsible for the size
bloat. I tried both a quick format and a full format, but
either way, it tried and then gave up saying "Unable to
complete format." or something very close to that. I know
you can't covert an NTFS file system back to FAT32, but I
thought that I could at least reformat it back if I didn't
care about the contents (of which there were none). So, I
don't understand that either.

Finally, in the research that I've done since, I've noted
several places that say that in WinXP, one can't create a
FAT32 file system larger than 32GB. I don't remember if
that limit also exists for Win2K, but if it does, then
that is probably why I can't reformat those 58.4GB
partitions using FAT32. But, then, I have to wonder why
the OS even gives me that option when it already knows the
size of the partition.

If FAT32 is always limited to a maximum of 32GB, then I
also have to ask how it is that I was able to create a
120GB FAT32 partition under Win98se. Perhaps there was
some magic done by the disk controller on that system that
made this possible. Its been so long since I installed
that drive that I no longer remember the details, but if
that's the case, the perhaps that disk controller magic is
also responsible for the storage efficiency of that system.

I'd be most grateful for any light that anyone can shed on
any of these mysteries.

There must be something missing here because you would not have had a 4k
cluster size even on FAT32 with your size partitions. Here are the
defaults.

512 MB to 8,191 MB 4 KB
8,192 MB to 16,383 MB 8 KB
16,384 MB to 32,767 MB 16 KB
Larger than 32,768 MB 32 KB

There is a limit of 32 gig when creating FAT32 in Windows 2000 and
Windows XP.

NTFS is always more space efficient than FAT32 except on small
partitions where the MFT creates more overhead.

I would not leave the NTFS partition with 512 byte cluster size. It will
have more overhead in access and in the MFT.

Leonard Severt

Windows 2000 Server Setup Team
 
R

R. C. White

Hi, Bob.

In your research, you must have missed the Win2K Pro Resource Kit. You can
read the online version here:

http://www.microsoft.com/windows200...techinfo/reskit/en-us/prork/prdf_fls_pxjh.asp

The Maximum Size Limitations page tells us, among other things, that
Microsoft has imposed the 32 GB limit on formatting volumes as FAT32. It
also says (sorry about the line formatting in OE):
Maximum volume size 32 GB (This is due to the Windows 2000 Format
tool. The maximum volume size that Windows 98 can create is 127.53 GB).



To read the entire chapter, including a discussion and comparison of cluster
sizes, go to System Configuration and Management and expand the File Systems
chapter heading from the Table of Contents on the left of the screen (click
"show toc" if it is not visible).

RC
 

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