From: Eric Sandeen <sandeen@redhat.com>
Subject: Re: [PATCH RFC] jbd: don't wake kjournald unnecessarily
Date: Fri, 21 Dec 2012 11:01:58 -0600
Message-ID: <50D49606.3020708@redhat.com>
References: <50D0A1FD.7040203@redhat.com> <20121219012710.GF5987@quack.suse.cz> <20121219020526.GG5987@quack.suse.cz> <50D12FC3.6090209@redhat.com> <20121219081334.GB20163@quack.suse.cz> <20121219153725.GD7795@thunk.org> <20121219171401.GB28042@quack.suse.cz> <20121219202734.GA18804@thunk.org>
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Cc: Jan Kara <jack@suse.cz>,
	ext4 development <linux-ext4@vger.kernel.org>
To: "Theodore Ts'o" <tytso@mit.edu>
In-Reply-To: <20121219202734.GA18804@thunk.org>
Sender: linux-ext4-owner@vger.kernel.org

On 12/19/12 2:27 PM, Theodore Ts'o wrote:
> On Wed, Dec 19, 2012 at 06:14:01PM +0100, Jan Kara wrote:
>>   I agree. Just I'm still somewhat puzzled by those two reports pointed to
>> by Eric. In both cases stored tids were 0 and I cannot see how that happens
>> (well how it could happen in a reasonably likely way).
> 
> I'm also really puzzled about how Eric's patch makes a 10% different
> on the AIM7 benchmark; as you've pointed out, that will just cause an
> extra wakeup of the jbd/jbd2 thread, which should then quickly check
> and decide to go back to sleep.
> 
> 					- Ted
> 

Ted, just to double check - is that some wondering aloud, or a NAK
of the original patch? :)

-Eric