From: Marc MERLIN <marc@merlins.org>
To: linux-btrfs@vger.kernel.org
Cc: mfasheh@suse.de
Subject: Workaround for hardlink count problem?
Date: Sat, 8 Sep 2012 09:56:20 -0700 [thread overview]
Message-ID: <20120908165620.GA17951@merlins.org> (raw)
I read the discussions on hardlinks, and saw that there was a proposed patch
(although I'm not sure if it's due in 3.6 or not, or whether I can apply it
to my 3.5.3 tree).
I was migrating a backup disk to a new btrfs disk, and the backup had a lot of hardlinks
to collapse identical files to cut down on inode count and disk space.
Then, I started seeing:
cp: cannot create hard link `../dshelf3/backup/saroumane/20080319/var/lib/dpkg/info/libaspell15.postrm' to `../dshelf3/backup/moremagic/oldinstall/var/lib/dpkg/info/libncurses5.postrm': Too many links
cp: cannot create hard link `../dshelf3/backup/saroumane/20080319/var/lib/dpkg/info/libxp6.postrm' to `../dshelf3/backup/moremagic/oldinstall/var/lib/dpkg/info/libncurses5.postrm': Too many links
cp: cannot create symbolic link `../dshelf3/backup/saroumane/20020317_oldload/usr/share/doc/menu/examples/system.fvwmrc': File name too long
cp: cannot create hard link `../dshelf3/backup/saroumane/20061218/var/lib/dpkg/info/libxxf86vm1.postrm' to `../dshelf3/backup/moremagic/oldinstall/var/lib/dpkg/info/libncurses5.postrm': Too many links
cp: cannot create hard link `../dshelf3/backup/saroumane/20061218/var/lib/dpkg/info/libxxf86dga1.postrm' to `../dshelf3/backup/moremagic/oldinstall/var/lib/dpkg/info/libncurses5.postrm': Too many links
cp: cannot create hard link `../dshelf3/backup/saroumane/20061218/var/lib/dpkg/info/libavc1394-0.postrm' to `../dshelf3/backup/moremagic/oldinstall/var/lib/dpkg/info/libncurses5.postrm': Too many links
What's interesting is the 'File name too long' one, but more generally,
I'm trying to find a userspace workaround for this by unlinking files that go beyond
the hardlink count that btrfs can support for now.
Has someone come up with a cool way to work around the too many link error
and only when that happens, turn the hardlink into a file copy instead?
(that is when copying an entire tree with millions of files).
I realize I could parse the errors and pipe that into some crafty shell to do this,
but if there is a smarter already made solution, I'm all ears :)
Thanks,
Marc
--
"A mouse is a device used to point at the xterm you want to type in" - A.S.R.
Microsoft is to operating systems ....
.... what McDonalds is to gourmet cooking
Home page: http://marc.merlins.org/
next reply other threads:[~2012-09-08 16:56 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-09-08 16:56 Marc MERLIN [this message]
2012-09-10 9:12 ` Workaround for hardlink count problem? Martin Steigerwald
2012-09-10 9:21 ` Fajar A. Nugraha
2012-09-10 23:09 ` Martin Steigerwald
2012-09-10 23:38 ` Jan Engelhardt
2012-09-11 9:16 ` Martin Steigerwald
2012-09-11 14:20 ` Arne Jansen
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