From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757527AbeDXMwZ (ORCPT ); Tue, 24 Apr 2018 08:52:25 -0400 Received: from merlin.infradead.org ([205.233.59.134]:38376 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933222AbeDXMtA (ORCPT ); Tue, 24 Apr 2018 08:49:00 -0400 Date: Tue, 24 Apr 2018 14:48:55 +0200 From: Peter Zijlstra To: subhra mazumdar Cc: linux-kernel@vger.kernel.org, mingo@redhat.com, daniel.lezcano@linaro.org, steven.sistare@oracle.com, dhaval.giani@oracle.com, rohit.k.jain@oracle.com Subject: Re: [PATCH 3/3] sched: limit cpu search and rotate search window for scalability Message-ID: <20180424124855.GT4082@hirez.programming.kicks-ass.net> References: <20180424004116.28151-1-subhra.mazumdar@oracle.com> <20180424004116.28151-4-subhra.mazumdar@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180424004116.28151-4-subhra.mazumdar@oracle.com> User-Agent: Mutt/1.9.3 (2018-01-21) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Apr 23, 2018 at 05:41:16PM -0700, subhra mazumdar wrote: > Lower the lower limit of idle cpu search in select_idle_cpu() and also put > an upper limit. This helps in scalability of the search by restricting the > search window. Also rotating the search window with help of next_cpu > ensures any idle cpu is eventually found in case of high load. So this patch does 2 (possibly 3) things, that's not good.