From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9FA1A374F1 for ; Wed, 30 Oct 2024 11:01:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=90.155.92.199 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730286067; cv=none; b=cXm/UwSehTgnjYf6tg3zNUMlJRqR/LlCGBy0nKQ6xnVdqCa1LWLYnLCSigxqARjmkEe3U9fU9p9HY9dsRuBGRtrkQZTyhWrpMerxGXJ675Ugj8QmmZ8LKcdKF0LoX8Fim6HIA+EBIufNWHDdsvOqWZweV9tpl2kYuI1uVkM2gSU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730286067; c=relaxed/simple; bh=FdqQgkr6nyj5UIrSkVF1FPhTvx2Ly5K1TjMARDT8dtU=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=WayolVvKBr2/eX3prvByOSwxp2Bp4W/+K17r6lw63fk/8jcsPIczPAfageGroca+Qm5gQA6e9St02ewLFPKRE5BUcdU3u9NqBExdRVL3q04lzbwoQsxDdzcDs6zKn0yZz5kFxyRU20T42FGuZbvJmnW/7E0B7DcKeZEcbt0lYyg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=Dgi1j5mU; arc=none smtp.client-ip=90.155.92.199 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="Dgi1j5mU" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=dro8xWc27MCENjI9Eb4iLkZ+EZf2BtDA/T4dTqKV1oQ=; b=Dgi1j5mUIc6SAPmt1FmNEGw0Uj JiNl9PkPCPAmN1G/PB3XO/svCGSUkH2oO4iYCH5eMKg+JQXKEvNB2wsJAts9wDI4L5W+IyQHCr8WS eWT1Yu3vUlxHKZi77uxCwfTJhyft5RpHHZJa1M7rPkHqS7fysC0ghzGRmU573CK1pAQfEELXLb/Al cwAw7YoNrBFkivxvJ/dQYzoOO3tUAdn13uuKAqooWTQoJ0CGOGisSRc2nk/8ky/oc7W2fLQa9tqSj Boo2ZLhrD6BryBWYPnMQLTfX/6kyyMX7aucFCSRp26M3PnyLNYEWBQHDOY5uN6+3CV69cQ58JQwCa Dtrf40tg==; Received: from j130084.upc-j.chello.nl ([24.132.130.84] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.98 #2 (Red Hat Linux)) id 1t66Rc-0000000AEOV-357N; Wed, 30 Oct 2024 11:00:56 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id 62073300ABE; Wed, 30 Oct 2024 12:00:56 +0100 (CET) Date: Wed, 30 Oct 2024 12:00:56 +0100 From: Peter Zijlstra To: Tianchen Ding Cc: linux-kernel@vger.kernel.org, Ingo Molnar , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Valentin Schneider , Tejun Heo Subject: Re: [RFC PATCH 2/2] sched/eevdf: Introduce a cgroup interface for slice Message-ID: <20241030110056.GL14555@noisy.programming.kicks-ass.net> References: <20241028063313.8039-1-dtcccc@linux.alibaba.com> <20241028063313.8039-3-dtcccc@linux.alibaba.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20241028063313.8039-3-dtcccc@linux.alibaba.com> On Mon, Oct 28, 2024 at 02:33:13PM +0800, Tianchen Ding wrote: > Introduce "cpu.fair_slice" for cgroup v2 and "cpu.fair_slice_us" for v1 > according to their name styles. The unit is always microseconds. > > A cgroup with shorter slice can preempt others more easily. This could be > useful in container scenarios. > > By default, cpu.fair_slice is 0, which means the slice of se is > calculated by min_slice from its cfs_rq. If cpu.fair_slice is set, it > will overwrite se->slice with the customized value. So I'm not sure I like to expose this, like this. The thing is, this is really specific to the way we schedule the cgroup mess, fully hierarchical. If you want to collapse all this, like one of those bpf schedulers does, then you cannot do this.