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Date: Wed, 25 Mar 2009 17:51:37 -0400
From: Theodore Tso <tytso@mit.edu>
To: Linus Torvalds <torvalds@linux-foundation.org>
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Subject: Re: Linux 2.6.29
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On Wed, Mar 25, 2009 at 01:45:43PM -0700, Linus Torvalds wrote:
> > The third potential solution we can try doing is to make some tuning
> > adjustments to the VM so that we start pushing out these data blocks
> > much more aggressively out to the disk.
> 
> Yes. but at least one problem is, as mentioned, that when the VM calls 
> writepage[s]() to start async writeback, many filesystems do seem to just 
> _block_ on it.

Um, no, ext3 shouldn't block on writepage().  Since it doesn't do
delayed allocation, it should always be able to push out a dirty page
to the disk.

						- Ted