linux-kernel - Re: [PATCH v2 1/3] sched/fair: fix rounding issue for asym packing

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CAKfTPtDwUqf1tKxOkJ-rU2FHUL63=smEtCRu5dqwYZC7zjvtJw@mail.gmail.com>
Date:   Wed, 19 Dec 2018 16:20:27 +0100
From:   Vincent Guittot <vincent.guittot@...aro.org>
To:     Valentin Schneider <valentin.schneider@....com>
Cc:     Peter Zijlstra <peterz@...radead.org>,
        Ingo Molnar <mingo@...nel.org>,
        linux-kernel <linux-kernel@...r.kernel.org>,
        Morten Rasmussen <Morten.Rasmussen@....com>
Subject: Re: [PATCH v2 1/3] sched/fair: fix rounding issue for asym packing

On Wed, 19 Dec 2018 at 16:11, Valentin Schneider
<valentin.schneider@....com> wrote:
>
> On 19/12/2018 15:05, Vincent Guittot wrote:
> [...]
> >> True, I had a look at the trace and there doesn't seem to be any running
> >> task on that CPU. That's a separate matter however - the rounding issues
> >> can happen regardless of the wl values.
> >
> > But it means that the rounding fix +1 works and your problems comes
> > from something else
>
> Oh yes, I never said it didn't work - I was doing some investigation on
> the reason as to why we'd need this fix, because it's wasn't explicit from
> the commit message.
>
> The rounding errors are countered by the +1, yes, but I'd rather remove
> the errors altogether and go for the snippet I suggested in my previous
> reply.

except that you don't always want to migrate all group load.
I prefer keeping current algorithm and fix it for now. Trying "new"
thing can come in a 2nd step