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 E08743C0F for ; Mon, 27 Mar 2023 15:18:44 +0000 (UTC) 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=qw5bqjgcS2x0FZITiKwR5inM/4awzH/SqXKldpvrD4o=; b=SOfZ7Idu/V84y1K6baWNSU0LFp Z6eb62XHHaghSpEFygofomxFnvR0krPcQ3/TCcVM4GRZAGiGH01hFnlVE9tEL50MigGeSUbP+ILgy Me1Ik1Vk4+8aAzRihA3+TqBckX8HBHnNezC2IXx+EiV3gq1uvM05SOTE0w1AOYgAz9rbgjPXt9Ivf Nx9DySzhaN/vHQSwgGz7sPBW7yH473YKWFpc7X3FnKzAiZwoZaAWDoobH7nnWFZ52hbB+cPlMEwiF B/XsjMyRvZUzgKn5gkEhisXzityuikQ+THbJqVEW4QkWl/bSHCrCONBKaV2DRMD+pVkdcTMI+5HI5 2whk1JPg==; Received: from j130084.upc-j.chello.nl ([24.132.130.84] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.96 #2 (Red Hat Linux)) id 1pgoc9-006D9t-0A; Mon, 27 Mar 2023 15:18:29 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 412D13002FC; Mon, 27 Mar 2023 17:18:26 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 2954320C0F36C; Mon, 27 Mar 2023 17:18:26 +0200 (CEST) Date: Mon, 27 Mar 2023 17:18:26 +0200 From: Peter Zijlstra To: Chen Yu Cc: oe-lkp@lists.linux.dev, lkp@intel.com, Oliver Sang , Chen Yu , Ingo Molnar Subject: Re: [peterz-queue:sched/eevdf] [sched/fair] 23669fce72: aim7.jobs-per-min -18.6% regression Message-ID: <20230327151826.GC11425@hirez.programming.kicks-ass.net> References: <202303201517.399a9b16-oliver.sang@intel.com> <20230320075850.GA2194297@hirez.programming.kicks-ass.net> <20230321090318.GB2234901@hirez.programming.kicks-ass.net> <20230326110024.GA2990748@hirez.programming.kicks-ass.net> <20230326133851.GA2994912@hirez.programming.kicks-ass.net> Precedence: bulk X-Mailing-List: oe-lkp@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Mon, Mar 27, 2023 at 09:39:25PM +0800, Chen Yu wrote: > I'll launch more tests tomorrow with/without PLACE_BONUS. Right, so it will absolutely destroy a number of workloads.. I've not yet found a way to write that thing without it wrecking things. Fundamentally the problem seems to be that if you place entities so far back the whole latency thing goes out the window. Specifically, becuse it did not in fact content that whole time, it is now significantly behind and needs to catch up, but it cannot do that while also respecting latency requirements of the existing tasks.