Date: Wed, 23 Nov 2016 16:59:58 -0800
From: Shaohua Li <shli@fb.com>
To: Tejun Heo <tj@kernel.org>
CC: <linux-block@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        <Kernel-team@fb.com>, <axboe@fb.com>, <vgoyal@redhat.com>
Subject: Re: [PATCH V4 09/15] blk-throttle: make bandwidth change smooth
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On Wed, Nov 23, 2016 at 04:23:35PM -0500, Tejun Heo wrote:
> Hello,
> 
> On Mon, Nov 14, 2016 at 02:22:16PM -0800, Shaohua Li wrote:
> > cg1/cg2 bps: 10/80 -> 15/105 -> 20/100 -> 25/95 -> 30/90 -> 35/85 -> 40/80
> > -> 45/75 -> 10/80
> 
> I wonder whether it'd make sense to make the clamping down gradual too
> (way faster than the ramping up but still gradual).  The control model
> isn't immediate anyway and doing the other direction gradually too
> might not hurt the overall control accuracy all that much.

Sure, that's in my todo list. Part of the reason is I didn't figure out an easy
to do it. I'll keep trying later.

Thanks,
Shaohua