Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758678Ab3GZQzR (ORCPT ); Fri, 26 Jul 2013 12:55:17 -0400 Received: from mail-ob0-f182.google.com ([209.85.214.182]:38755 "EHLO mail-ob0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756835Ab3GZQzN (ORCPT ); Fri, 26 Jul 2013 12:55:13 -0400 MIME-Version: 1.0 In-Reply-To: <20130726102240.GA30786@mtj.dyndns.org> References: <1374749531-16423-1-git-send-email-laijs@cn.fujitsu.com> <20130725153121.GF26107@mtj.dyndns.org> <51F1DB45.90905@cn.fujitsu.com> <20130726030711.GA30195@mtj.dyndns.org> <51F1F138.2060902@cn.fujitsu.com> <20130726102240.GA30786@mtj.dyndns.org> Date: Sat, 27 Jul 2013 00:55:12 +0800 Message-ID: Subject: Re: [PATCH] workqueue: clear workers of a pool after the CPU is offline From: Lai Jiangshan To: Tejun Heo , Lai Jiangshan Cc: linux-kernel@vger.kernel.org Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1309 Lines: 37 On Fri, Jul 26, 2013 at 6:22 PM, Tejun Heo wrote: > On Fri, Jul 26, 2013 at 11:47:04AM +0800, Lai Jiangshan wrote: >> any worker can't kill itself. >> managers always tries to leave 2 workers. >> >> so the workers of the offline cpu pool can't be totally destroyed. > > But we *do* want to keep them around as CPUs taken offline are likely > to come online at some point and destroying all of them saves only > ~16k of memory while adding more work while CPUs are on/offlined which 4 threads, (normal and high priority wq) ~32k it is still small. > can be very frequent on mobile devices. The change was *intentional*. but sometimes the cpu is offline for long time. and maybe the adminstrator want to reclaim the resource.. Add a boot option or sysfs switch? > > Thanks. > > -- > tejun > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/