From mboxrd@z Thu Jan  1 00:00:00 1970
From: Chris Mason <mason@suse.com>
Subject: Re: [linux-lvm] snapshots of busy ext2 file system corrupt
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Date: Tue Feb 26 14:58:02 2002
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On Tuesday, February 26, 2002 08:28:40 PM +0100 Urs Thuermann <urs@isnogud.escape.de> wrote:

> Chris Mason <mason@suse.com> writes:
> 
>> For ext2, the best we could do would probably be a hack based on 
>> locking the super.  As far as I know, nobody is planning on this,
> 
> :-(
> 
>> especially given how easy it is to go from ext2->ext3.
> 
> Some performance tests I made with ext2, ext3, and reiserfs convinced
> me to stay with ext2.  ext3 was significantly slower than ext2 on some
> operations (and reiserfs even worse than that).

You trade speed for safety sometimes, but you can lower the performance
hit by mounting ext3 with -o data=writeback, and help both filesystems
by playing with bdflush values (increment the metadata timeout up from 5
seconds).

Other tuning depends on your app.

-chris