Subject: Re: Undelete for linux? From: amoss@picton.cs.huji.ac.il (Amos Shapira) Date: 28 Jul 1993 13:31:19
rohrer@fncrd6.fnal.gov (Keith Rohrer) writes:
I saw that in the documentation for ext2, probably the 0.3 version; I for
one would really love to see a defragger before compression even comes into
play. Preferably one that syncs at the right times--unless there's already
a way to tell the buffer cache "Hey, I'm doing large block transfers, if
you don't deal with this, the drive is going to start spending 99% of its
time doing silly seeks...".
There is a defragger for IRIX efs, for instance, they just run it once a week
during the weekend. This isn't DOS you know :).
Also I have no idea how ext2fs does what it does but the biggest impruvment
in BSD 4.2 which gave it its place in the holl of fame was the special Fast
File System which was smart enough to move blocks around as the files grew
and shrunk and plan the block allocation according to heauristics which
prevent fragmantation altogether, we could run our VAX 750 for years without
having to defrag the disks and with mean fragmantaion of less than 3%.
Compression would be good, too, especially if
it were fast, especially if it were enabled and disabled based on names?
Like, say anything .gz, .tgz, .lha, .lzh, .zoo, .zip, &c, doesn't get
compressed, anything .txt does... Specifying compression by directory
and by name (incl. wildcard match) will be vital, imho. It might be good to
have a this-file-does-not-compress-well bit the fs could set, too...
You seem to think in DOS terms again. So far I supposed people were talking
about compression in the kernel level, which means the kernel deals with
i-nodes not with file names. What if a file have two hard links, one with
".tgz" and one with ".txt"? I don't see such a scheme becoming a reality and
if it does then I would reconsider using Linux as it will head stright on the
path of behemoth like VM, VMS, NOS-BE etc. were the kernel does EVERYTHING for
you whether you like it or not.
People keep forgeting one of the basic blocks of the UNIX phylosophy: if
you can do it outside the kernel then don't put it in.
Cheers,
--Amos