From: David Laight <david.laight.linux@gmail.com>
To: Qais Yousef <qyousef@layalina.io>
Cc: Ingo Molnar <mingo@kernel.org>,
Peter Zijlstra <peterz@infradead.org>,
Vincent Guittot <vincent.guittot@linaro.org>,
Juri Lelli <juri.lelli@redhat.com>,
Steven Rostedt <rostedt@goodmis.org>,
John Stultz <jstultz@google.com>,
Thomas Gleixner <tglx@kernel.org>,
Frederic Weisbecker <frederic@kernel.org>,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH 0/3] sched/tick: Decouple sched_tick() from HZ
Date: Sun, 17 May 2026 15:10:41 +0100 [thread overview]
Message-ID: <20260517151041.10a9a355@pumpkin> (raw)
In-Reply-To: <20260517040740.444729-1-qyousef@layalina.io>
On Sun, 17 May 2026 05:07:37 +0100
Qais Yousef <qyousef@layalina.io> wrote:
> Previous attempt to make HZ 1000 the default [1] to help with scheduler
> responsiveness didn't get merged. But maybe for the best, as I think this idea
> of decoupling sched_tick() from HZ makes more sense. We shouldn't need to make
> a choice between how often timers should trigger vs how often should the
> scheduler update its stats/take decisions.
Have you also looked a decoupling HZ/jiffies from the timer interrupt rate?
It ought to be reasonable set HZ to 1000 and to do 'jiffies += 4' when the
timer interrupts 250 times a second.
I'd expect most code to handle that fine.
I know one architecture (forgotten which) traditionally used a 1024Hz clock,
and some very old ones 60Hz; but I don't think Linux supports either.
-- David
next prev parent reply other threads:[~2026-05-17 14:10 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-05-17 4:07 Qais Yousef
2026-05-17 4:07 ` [PATCH 1/3] " Qais Yousef
2026-05-17 4:07 ` [PATCH 2/3] sched/tick: Move TICK_NSEC users to PTICK_NSEC Qais Yousef
2026-05-17 4:07 ` [PATCH 3/3] sched/tick: Turn on PTICK by default Qais Yousef
2026-05-17 4:19 ` [PATCH 0/3] sched/tick: Decouple sched_tick() from HZ Qais Yousef
2026-05-17 14:10 ` David Laight [this message]
2026-05-17 15:44 ` Qais Yousef
2026-05-17 16:09 ` David Laight
2026-05-17 17:26 ` Qais Yousef
2026-05-18 7:40 ` Peter Zijlstra
2026-05-19 0:42 ` Qais Yousef
2026-05-19 9:13 ` Peter Zijlstra
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20260517151041.10a9a355@pumpkin \
--to=david.laight.linux@gmail.com \
--cc=frederic@kernel.org \
--cc=jstultz@google.com \
--cc=juri.lelli@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@kernel.org \
--cc=peterz@infradead.org \
--cc=qyousef@layalina.io \
--cc=rostedt@goodmis.org \
--cc=tglx@kernel.org \
--cc=vincent.guittot@linaro.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
Powered by JetHome