> From: Pavel Machek <pavel@suse.cz>
> Date: Thu, 2 Mar 2000 23:40:32 +0100
> Subject: Re: [OT] Microsoft invents symbolic links
>
> Actually, 40% of my disk capacity is wasted in duplicates. Why? I do cp
> -a linux linux.backup before major changes. Automagicall ways to get
I can't even guess what the ratio is on a small companys (like ours) file
server filled with old source versions and documents copies.
> space back would be nice. (I also cp -a package ofic.package, so that I
> can diff -ur later... Hardlinks are not enough because I do not want to
> accidentaly trash ofic.)
>
> So, I'd actually like cow-link. cp -a --cow-link mc ofic.mc would be
> very usefull for me.
I second that. We do incremantal backups with
cp -al yesterdays-backup/ todays-backup/
rsync --archive --hard-links --whole-file --delete /backed-up-dir todays-backup
Of course, that works just fine (with very good disk space usage, since we
also use e2compr). But with cow-links, you could backup your working
(source, document, image) directory and not worry about disk space usage
or your editor creating new inode on save.
On file servers there definetely are a lot of duplicates. Text documents,
source, images tend to be duplicated - people have their personal copies.
People hacking on source have multiple copies of it.
You could have a cowlinkd running nightly on file server and finding and
cow-linking those duplicates. (It could e2compr less used files as well).
Of course, to get the most out of the redundancy in, say, document or
source tree, the cow-scheme would have to be on block level rather than
inode level (as it is page level in vm). I suppose that just wouldn't even
theoretically be affortable, since it would propably take per-block
reference counting.
-- v --
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.tux.org/lkml/
This archive was generated by hypermail 2b29 : Tue Mar 07 2000 - 21:00:16 EST