Re: Modified FAT filesystem

Albert Cahalan (
Fri, 22 Nov 1996 18:36:52 -0500 (EST)

From: Gordon Chaffee <>
> Albert Cahalan <> wrote:
>> Right now, mtools is 4x as fast as the kernel filesystem.
>> I tested a file copy of 700 kB on a 1.44 MB floppy disk and
>> a file copy of 4 MB on a 96 MB Zip disk. In both cases,
>> mtools was about 4x faster.
> I ran a couple tests, and I didn't see a 4x difference, but
> mtools would usually win. The most dramatic difference I saw
> was on a 45 MB file.
> mtools: 35.66 seconds to write file.
> fat: 87.49 seconds to write file.
> So mtools in this case is 2.5x faster than the kernel fat code.

In my tests, both source and destination were on the same fat
filesystem. I flushed the disk cache before each test by using
a program that mallocs and changes 4 kB chunks until it crashes.

The speed difference may be related to the ratio between disk
bandwidth and seek time. I would expect interesting results from
a test of large files on optical cartridges.