From mboxrd@z Thu Jan  1 00:00:00 1970
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Subject: Re: testing io.low limit for blk-throttle
To: Paolo Valente <paolo.valente@linaro.org>
Cc: linux-block <linux-block@vger.kernel.org>, Jens Axboe <axboe@kernel.dk>,
        Shaohua Li <shli@fb.com>, Mark Brown <broonie@kernel.org>,
        Linus Walleij <linus.walleij@linaro.org>,
        Ulf Hansson <ulf.hansson@linaro.org>
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 <cbd82e3d-4465-864d-c057-898135626362@oracle.com>
 <94F005D5-EC8B-4830-AD5B-489117F7DC60@linaro.org>
From: "jianchao.wang" <jianchao.w.wang@oracle.com>
Message-ID: <5921aa86-37d9-a85d-18da-ff363ff83cf2@oracle.com>
Date: Mon, 23 Apr 2018 14:35:04 +0800
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Hi Paolo

On 04/23/2018 01:32 PM, Paolo Valente wrote:
> Thanks for sharing this fix.  I tried it too, but nothing changes in
> my test :(> 

That's really sad.

> At this point, my doubt is still: am I getting io.low limit right?  I
> understand that an I/O-bound group should be guaranteed a rbps at
> least equal to the rbps set with io.low for that group (of course,
> provided that the sum of io.low limits is lower than the rate at which
> the device serves all the I/O generated by the groups).  Is this
> really what io.low shall guarantee?

I agree with your point about this even if I'm not qualified to judge it.

On the other hand, could you share your test case and blk-throl config here ?

Thanks
Jianchao