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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 06:34:32PM -0700, Linus Torvalds wrote:
> 
> Of course, the approach of just checking whether the buffer heads already 
> exists and are mapped (before bothering with anything else) probably works 
> fine in practice. In most loads, pages will have been dirtied by regular 
> "write()" system calls, and then we will have the buffers pre-allocated 
> regardless. 
> 

Yeah, I agree; solving the problem in the case of files being dirtied
via write() is going to solve a much percentage of the cases compared
to those cases where the pages are dirtied via mmap()'ed pages.

I thought we were doing this already, but clearly I should have looked
at the code first.  :-(

						- Ted
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