Max File Size On Disk (NTFS Vs. FAT)
This morning, WL called and woke me up in the morning to ask a very good question.
“How come a file that is 16GB can be stored on NTFS but when attempting to copy to FAT32, it complains that file is too big?”
- WL -
Before we get to the reason why, lets have a little history lesson first. NTFS and FAT32 are different formats for the Windows file system (read: filing system on your harddisk). Windows has in fact introduced and employed various file systems throughout its years, namely FAT12, FAT16, FAT32, and NTFS (versions ranging from NTFS1.0 through to NTFS5.0 and 5.1).
The FAT in FAT12, FAT16, and FAT32 stands for File Allocation Table and was designed for Microsoft’s operating systems starting with MS Disk BASIC, evolving through MS-DOS, adopted for Windows 95 through to Windows ME, and presently being used in Windows NT, Windows 2000, and Windows XP for varying reasons. The main reason why FAT is still a popular file system and widely in use is because of its relative simplicity and wide support by virtually all existing operating systems.
NTFS on the other hand stands for New Technology File System was introduced with the advent of Windows NT way back in 1993. Microsoft introduced NTFS as a replacement for the aging FAT system with various improvements and enhancements, including (but not limited to) enhanced security features, support for large file volumes and file sizes, compression, and encryption. It provided Microsoft’s future OSes with a more stable base for storage.
However, the drawback of NTFS was that older versions of Windows do not support, nor can they natively read, NTFS. This raises some compatibility and portability issues. It is largely due to this that portable media tend to be formatted using FAT instead of adopting NTFS. And that brings us back to the question that woke me up this morning.
FAT32 (32-bit File Allocation Table, which is the defacto FAT format, unless you’re running some uber old system) is limited in some aspects. In this particular case, the specific limit is in the maximum supported file size. While the maximum size of a file stored on a NTFS file is limited only by available storage space, FAT32 has a size cap of 4GB. It is obvious then, why Windows spits out an insufficient space error when attempting to copy a 16GB file from a harddisk formatted in NTFS to one in FAT32 format. The file system does not support such a large file size. To protect itself, Windows throws a tantrum.
So now we know why. As to which file system to use and performance issues? Well, that’s solely up to your descretion and needs, and are subjects for a different article. Too bad I can’t go back to bed ;)
Some light reading:
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Simonsays Said,
December 28, 2005 @ 4:48 pm
Size Limitations in NTFS and FAT File Systems
And with NTFS, you get max 16 terrabytes of data, something you definitely can’t copy to FAT32. If you happen to have a 20 TB divx file :) try XFS on Linux, as the filesystem can take 8 exabytes max per file :) See http://www.suse.de/~aj/linux_lfs.html
gbyeow Said,
December 28, 2005 @ 11:02 pm
The point of the matter is that Linux file systems are non-portable and not widely supported. Not every average Joe know how to read and write from raw diskspace. Granted that it may be a stable OS but that doesn’t mean that it isn’t the minority. FAT32 is supported by practically every mainstream OS available. And that is precisely the reason why it is still widely used. Its not about the size.
Simonsays Said,
December 29, 2005 @ 10:13 am
I don’t think that portability is a problem from within Windows and other mainstream OSes.
Reasons:
1. XFS can be accessed by Windows (and any other OS that supports the SMB protocol, ie. “Network Places”) via Samba.
2. Windows XP can directly read an ext2/3 partition using Explore2fs.
So yes, I can format a 4GB Flash drive with ext2/3 and still “see” it (and write to it) from XP, although without the Windows Explorer interface, lah. Too bad, have to sacrifice a lil bit lor.
I also think it’s about time the average Joe knows more about computing choices out there, as I don’t regard ignorance as a virtue :)
Simonsays Said,
December 29, 2005 @ 10:42 am
BTW I must agree with you that FAT32 is by far the most common filesystem around. The SD Card on my PDA, for example uses FAT.
FYI, I have tried both SMB access (from Linux, Mac & Windows boxes) and Explore2fs out before. It’s not that hard, plus all the info needed is available off the ‘Net :).
gbyeow Said,
December 29, 2005 @ 11:23 am
Remember that Windows is not only about NT based Windows (XP, 2000…). There’s still a large user base for ME, 98SE, 98, and (believe it or not) 95. Companies are putting off upgrades because of prior investments and future costs.
Alot of people just want things to work. They are not too interested in finding out why or how it works. It is not ignorance. It is simply not in their interest to go through the paces. This is especially true in a world where deadlines and delivery takes centre stage.
From a corporate viewpoint, it is foolish to adopt a standard that is not widely supported. It doesn’t matter that it is the ‘better’ standard. What matters that their business partners and customers might not be able to read files from their storage media. And that is just bad business sense. They’ve read their history, learned their lesson, and fear the consequences of adopting new technology, especially technology dealing with something as simplistic as data storage.
The very point that you brought up about sacrificing the explorer interface is, on its own, a good enough deterrent for people.
We’re digressing. The topic is moving into discussions of ideals. Ideals does not make the world go round, although if it was, then the world would be a better place for it.
Boredworkers.com » Windows Disk Management Said,
January 20, 2006 @ 9:30 am
[…] Follow the instructions on screen, specifying a suitable size for the partition amd a preferred file format (either FAT32 or NTFS) […]
Arvin Said,
May 19, 2006 @ 9:53 am
Go back to work, you bored workers!
bijendra Said,
January 8, 2007 @ 2:25 pm
i have a problem that my Ext protable harddrive ntfs so i want to convert ntfs to fat so give me a solution.
G: Let me see if I got this right. You want to convert your external harddrive from an NTFS file system to FAT32. There are exactly two ways that I can think of.
1. Backup the files on your drive, reformat the drive with FAT32 and restore your data files.
2. Use a third party software like Partition Magic.
Note that the second method usually causes more problems than it solves. It might introduce errors to your data or worse, erase them altogether. The safest method is to reformat. However, if reformating and third party software are not open options to you, then you’re stuck with NTFS for life.
Hope that helps. Let me know if you have other questions. I’ve assumed that you know how to format a drive so I haven’t included that information. If you don’t then leave another message and I’ll walk you through it.