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Wysocki" , Viresh Kumar , Juri Lelli , Steven Rostedt , Dietmar Eggemann , Tim Chen , "Chen, Yu C" , Thomas Gleixner , linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org Subject: Re: [PATCH v2 00/13] sched/fair/schedutil: Better manage system response time Message-ID: <20260512080157.ozdvvmezgkeurwbu@airbuntu> References: <20260504020003.71306-1-qyousef@layalina.io> Precedence: bulk X-Mailing-List: linux-pm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: On 05/11/26 10:58, John Stultz wrote: > On Sun, May 3, 2026 at 7:00 PM Qais Yousef wrote: > > > > This is the long delayed follow up to the series sent back in August 2024 [1]. > > Life got in the way to some extent (I had a baby, and now my time that I used > > to do upstream work late at night was stolen :). Apologies for those who > > replied and I didn't get a chance to respond back. > > > ... > > Open questions: > > > > * The details of the QoS interface is the biggest one. > > * Would debugfs be better for setting the default rampup multiplier instead of sysctl? > > * Patch 13 makes updating load_avg unconditional not on period boundaries. > > > > Patches 1-3 are prepatory patches renaming a function and introducing new ones. > > > > Patches 4-5 handle the magic margin problem but making them dynamic based on > > actual hardware limitations. > > > > Patches 6-7 fix the black hole problem and teaches the scheduler how to handle > > bursty and periodic tasks via extending util_est. > > > > Patches 8-9 is where I expect most of the discussion on as I introduce a new > > sched_qos interface to support the new rampup_multiplier to help manage DVFS. > > > > Patches 10-11 introduces a couple of necessary optimizations to counter the > > power impact of increased responsiveness by disabling some features that we now > > know how to handle better. > > > > Patches 12-13 fix a couple of issues causing util_est and util_avg value to > > swing for a periodic task. Patch 12 must go via stable. > > Just a minor nit, If 12/13 are fixes, should they not be at the front > of the series (or possibly sent separately) so they can potentially > move forward while the bigger changes in this series are discussed? Yeah my plan was to split it and repost it with proper Fixes tag. I found it while verifying my patches so lumped it at the end. Will repost as soon as I can.