Messages in this thread | | | Date | Mon, 13 Feb 2006 11:35:12 +0100 | From | Nicolas George <> | Subject | Re: Filesystem for mobile hard drive |
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Le quartidi 24 pluviôse, an CCXIV, Phillip Susi a écrit : > Ahh yes, the per file limit. BTW, why are you saying "To" and "Go" when > you apparently mean "TB" and "GB"?
I use the french word octet instead of byte, because it is less error prone (when you read "mb", does-it really mean megabit, or does it mean that the author is lazy about capitalization?) and a little bit more precise. Tough I actually am French, I did not start using a French word in English by myself. I copy a practice of the IETF: the RFCs use octet more than byte.
> The fat data structures do not encourage fragmentation any more or less > than ext2/3. NTFS is slightly better, more comparable to reiserfs than > ext2/3, but the difference is small. What causes massive fragmentation > is how the driver chooses to allocate new blocks as you write to files. > Microsoft has always used about the worst possible algorithm for doing > this you can imagine, which is why fragmentation has always been a big > problem on their OSes. Linux is smarter and allocates blocks such that > fragmentation is kept to a minimum.
I believe you about that.
> I have not done any testing, but I know no reason why it would be worse > than fat.
That is a very good point. If windows can read UDF on hard drives and not only DVD, UDF could probably supersede FAT completely.
Thank you for pointing me that direction.
> It does not do transaction logging, and there currently is no > fsck for it, so for safety reasons, it may not be such a good choice.
I have a Solaris 9 near at hand, and I see a /lib/fs/udfs/fsck, and in the source tarball of OpenSolaris, I find a directory usr/src/cmd/fs.d/udfs/fsck/. It does not compile out of the box, but it may be possible to port it with limited effort.
> I agree. I think the VFS layer should process the uid/gid options. By > default it should replace nobody with the specified id, and fat and ntfs > should just report all files as owned by nobody. Then a new option > should be added to force the translation for all ids, not just nobody.
I agree with that (except maybe for the NTFS part, which I do not know; let us just say "UID-less filesystems"). Maybe a full UID translation system similar th the one in NFS could be useful, or a generic hook for modules, but having basic UID overriding would be great.
Unfortunately, the VFS subsystem is something too complex for me at this time. [unhandled content-type:application/pgp-signature] | |