linux-kernel - Re: [PATCH BUGFIX RESEND 0/4] bfq: fix bugs breaking bandwidth guarantees occasionally

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Date:   Tue, 26 Jun 2018 18:23:40 +0200
From:   Holger Hoffstätte <holger@...lied-asynchrony.com>
To:     Paolo Valente <paolo.valente@...aro.org>,
        Jens Axboe <axboe@...nel.dk>
Cc:     linux-block@...r.kernel.org, linux-kernel@...r.kernel.org,
        ulf.hansson@...aro.org, broonie@...nel.org,
        linus.walleij@...aro.org, bfq-iosched@...glegroups.com,
        oleksandr@...alenko.name
Subject: Re: [PATCH BUGFIX RESEND 0/4] bfq: fix bugs breaking bandwidth
 guarantees occasionally

On 06/25/18 21:55, Paolo Valente wrote:
> Hi,
> during some bandwidth tests, I found some occasional but severe
> malfunctions (losses of bandwidth control). The first three patches in
> this series fix the bugs that caused these malfunctions. The last
> patch is a fix/improvement of the name of one of the functions
> involved with these bugs.
> 
> I guess these patches are appropriate for next kernel release.

Ran these overnight on 2 machines on top of recent BFQ and nothing
caught on fire. One funny benchmark result stood out since it gave
me (repeatedly!) 560 MB/s read bandwidth on an SSD which is rated to
do "up to 550MB/s", so I guess BFQ's bandwidth guarantees are now
really quite strong. :-)

Therefore:
Tested-by: Holger Hoffstätte <holger@...lied-asynchrony.com>

cheers,
Holger