Date: Tue, 26 Jun 2012 08:59:53 -0400
From: Vivek Goyal <vgoyal@redhat.com>
To: Josh Hunt <joshhunt00@gmail.com>
Cc: Tejun Heo <tj@kernel.org>, Jens Axboe <axboe@kernel.dk>,
        linux-kernel@vger.kernel.org
Subject: Re: multi-second application stall in open()
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On Mon, Jun 25, 2012 at 11:01:48PM -0500, Josh Hunt wrote:

[..]
> So this really seems like a problem with kblockd not kicking in. I've
> instrumented every path in select_queue and it's not getting hit after
> schedule dispatch. Everything seems to stall at that point until a new
> request comes in.

Ok, that's cool. So now we need to find out why queued work is not being
scheduled.

I think there are some workqueue related trace points. If you enable those
along with blktraces, that should give tejun some data to look at.

Thanks
Vivek
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