Subject: Re: [PATCH V7 00/18] blk-throttle: add .low limit
To: Shaohua Li <shli@fb.com>, Jens Axboe <axboe@kernel.dk>
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From: Jens Axboe <axboe@fb.com>
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Date: Mon, 27 Mar 2017 13:11:26 -0600
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On 03/27/2017 01:00 PM, Shaohua Li wrote:
> On Mon, Mar 27, 2017 at 12:15:29PM -0600, Jens Axboe wrote:
>> On 03/27/2017 11:51 AM, Shaohua Li wrote:
>>> V6->V7:
>>> - Don't overload blk stat, which will simplify the code. This will add extra
>>>   space in bio/request though with the low interface configure option on.
>>
>> Hmm, why? As far as I can see, it just makes things worse.
> 
> Part of the reason is the new callback based blk stat makes enabling stat less
> straightforward. I probably can create a fake callback and enalbing the stat
> though. Only the last 3 patches depend on this, if you prefer, I can resend
> them and add the overload back.

Yeah, I think that would be a big improvement.

-- 
Jens Axboe