From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.1 (2015-04-28) on archive.lwn.net X-Spam-Level: X-Spam-Status: No, score=-5.6 required=5.0 tests=DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI, T_DKIM_INVALID autolearn=ham autolearn_force=no version=3.4.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by archive.lwn.net (Postfix) with ESMTP id 657F37E677 for ; Wed, 2 May 2018 14:04:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751411AbeEBOCo (ORCPT ); Wed, 2 May 2018 10:02:44 -0400 Received: from merlin.infradead.org ([205.233.59.134]:56356 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751365AbeEBOCn (ORCPT ); Wed, 2 May 2018 10:02:43 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=merlin.20170209; 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:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=LM41facvwdAdcWlT+sVCARHogY3zOl1hiq5UQKcJaCY=; b=cUS4bgA6zI0xj359Td6zTURD0 148vvFKWkWWDVGNThKgtvKFotDDGf3kPvLbQOQLD2b5gOnVp5/xFAMpOfIMLtpntPVMvGmC1Cnum8 3dr6dJWyp/59YdX4QH/Rkp03xkYB1BQpL9hkQmQ846OrJ8nk+Pmk+GbQ5djourDJGt7rH1jAsv9ds XiiinU54TfAAjZfoy1UY7Ndf4SGvsoSV09KPExVWsrr16JXuchICDadPZoPn76cj/bAW30C9YGZ/3 zas1FUXOI7sjpct3zEPtmNL5xRf/NULdNnSzOsizTB50S5QvC+JnQXgsjKYEetFZVwf5/SmgdiIL8 /4b1ajwLg==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=hirez.programming.kicks-ass.net) by merlin.infradead.org with esmtpsa (Exim 4.90_1 #2 (Red Hat Linux)) id 1fDsKy-0001Dn-4V; Wed, 02 May 2018 14:02:28 +0000 Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id A6F3C2029FA14; Wed, 2 May 2018 16:02:26 +0200 (CEST) Date: Wed, 2 May 2018 16:02:26 +0200 From: Peter Zijlstra To: Waiman Long Cc: Tejun Heo , Li Zefan , Johannes Weiner , Ingo Molnar , cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, kernel-team@fb.com, pjt@google.com, luto@amacapital.net, Mike Galbraith , torvalds@linux-foundation.org, Roman Gushchin , Juri Lelli Subject: Re: [PATCH v7 2/5] cpuset: Add cpuset.sched_load_balance to v2 Message-ID: <20180502140226.GU12217@hirez.programming.kicks-ass.net> References: <1524145624-23655-1-git-send-email-longman@redhat.com> <1524145624-23655-3-git-send-email-longman@redhat.com> <20180502102416.GJ12180@hirez.programming.kicks-ass.net> <14d7604c-1254-1146-e2b6-23f4cc020b34@redhat.com> <20180502134225.GR12217@hirez.programming.kicks-ass.net> <94c80e1c-049d-6ec3-8e8c-40eb88d1341d@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <94c80e1c-049d-6ec3-8e8c-40eb88d1341d@redhat.com> User-Agent: Mutt/1.9.5 (2018-04-13) Sender: linux-doc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org On Wed, May 02, 2018 at 09:47:00AM -0400, Waiman Long wrote: > > I've read half of the next patch that adds the isolation thing. And > > while that kludges around the whole root cgorup is magic thing, it > > doesn't help if you move the above scenario on level down: > > > > > > R > > / \ > > A B > > / \ > > C D > > > > > > R: cpus=0-7, load_balance=0 > > A: cpus=0-1, load_balance=1 > > B: cpus=2-7, load_balance=0 > > C: cpus=2-3, load_balance=1 > > D: cpus=4-7, load_balance=1 > > > > > > Also, I feel we should strive to have a minimal amount of tasks that > > cannot be moved out of the root group; the current set is far too large. > > What exactly is the use case you have in mind with loading balancing > disabled in B, but enabled in C and D? We would like to support some > sensible use cases, but not every possible combinations. Suppose A is your system group, and C and D are individual RT workloads or something. Or suppose B has siblings and each group at that level is a delegate to a particular user/container. And the user/container in B happens to need 2 partitioned VMs or whatever. The idea is the same in all the examples, you want to allow sub-partitions. -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html