From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Hellwig <hch@infradead.org>
Subject: Re: [PATCH RFC] mm: Implement balance_dirty_pages() through waiting
 for flusher thread
Date: Tue, 22 Jun 2010 10:31:24 -0400
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Cc: Jan Kara <jack@suse.cz>, Dave Chinner <david@fromorbit.com>,
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To: Wu Fengguang <fengguang.wu@intel.com>
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On Tue, Jun 22, 2010 at 09:52:34PM +0800, Wu Fengguang wrote:
> 2) most writeback will be submitted by one per-bdi-flusher, so no worry
>    of cache bouncing (this also means the per CPU counter error is
>    normally bounded by the batch size)

What counter are we talking about exactly?  Once balanance_dirty_pages
stops submitting I/O the per-bdi flusher thread will in fact be
the only thing submitting writeback, unless you count direct invocations
of writeback_single_inode.