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Subject: Re: [PATCH 01/45] writeback: reduce calls to global_page_state in
 balance_dirty_pages()
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: Jan Kara <jack@suse.cz>
Cc: Wu Fengguang <fengguang.wu@intel.com>,
       Andrew Morton <akpm@linux-foundation.org>, Theodore Tso <tytso@mit.edu>,
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Date: Fri, 09 Oct 2009 17:18:32 +0200
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On Fri, 2009-10-09 at 17:12 +0200, Jan Kara wrote:
>   Ugh, but this is not equivalent! We would block the writer on some BDI
> without any dirty data if we are over global dirty limit. That didn't
> happen before.

It should have, we should throttle everything calling
balance_dirty_pages() when we're over the total limit.