From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH, RFC] Use WRITE_SYNC in __block_write_full_page() if
 WBC_SYNC_ALL
Date: Mon, 5 Jan 2009 10:47:13 -0800
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Cc: Jens Axboe <jens.axboe@oracle.com>, linux-ext4@vger.kernel.org,
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To: Theodore Tso <tytso@mit.edu>
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On Mon, 5 Jan 2009 09:47:40 -0500 Theodore Tso <tytso@mit.edu> wrote:

> there will be times (i.e., when we are doing a checkpoint as
> opposed to a commit, or in a fsync-heavy workload), where we will end
> up getting blocked behind kjournald, so upping the I/O priority really
> does make sense.

Not if it will cause kjournald writes to be prioritised ahead of any
reads, I suspect.  Writes are rarely synchronous, but with reads,
there's almost always someone waiting.