Messages in this thread | | | Date | Tue, 10 Apr 2007 11:44:51 -0500 | From | Matt Mackall <> | Subject | Re: Add a norecovery option to ext3/4? |
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On Tue, Apr 10, 2007 at 02:08:26PM +0200, Jörn Engel wrote: > On Tue, 10 April 2007 07:27:18 -0400, Theodore Tso wrote: > > > > I suppose what you could do is to read in the journal, and use it to > > create an remapping table so that when you want to read block #5126, > > and block number 5126 is in the journal, to read the journal version > > of the block instead of the one on disk. That would allow for safe > > access to a filesystem being mounted read-only without the journal > > being present. > > Another option would be to access the medium through a mapping inode, > replay the journal into the mapping inode and _not_ flush the dirty > pages. But as long as a remapping table is sufficient for ext3 journal > format, such a table should be simpler and faster.
Or you could make a snapshot with device-mapper and then mount it. Requires some free disk space somewhere (or a hack with loop on tmpfs), but should be doable today.
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