From mboxrd@z Thu Jan 1 00:00:00 1970 From: Glauber Costa Subject: Re: [PATCH] mm/memcg: add unlikely to mercg->move_charge_at_immigrate Date: Mon, 18 Jun 2012 17:09:36 +0400 Message-ID: <4FDF2890.3020004@parallels.com> References: <1340025022-7272-1-git-send-email-liwp.linux@gmail.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1340025022-7272-1-git-send-email-liwp.linux-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> Sender: cgroups-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: Content-Type: text/plain; charset="us-ascii"; format="flowed" To: Wanpeng Li Cc: Johannes Weiner , Michal Hocko , Balbir Singh , KAMEZAWA Hiroyuki , cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Gavin Shan On 06/18/2012 05:10 PM, Wanpeng Li wrote: > From: Wanpeng Li > > move_charge_at_immigrate feature is disabled by default. Charges > are moved only when you move mm->owner and it also add additional > overhead. How big is this overhead? That's hardly a fast path. And if it happens to matter, it will be just bigger when you enable it, and the compiler start giving the wrong hints to the code. From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx157.postini.com [74.125.245.157]) by kanga.kvack.org (Postfix) with SMTP id 0C59E6B004D for ; Mon, 18 Jun 2012 09:12:09 -0400 (EDT) Message-ID: <4FDF2890.3020004@parallels.com> Date: Mon, 18 Jun 2012 17:09:36 +0400 From: Glauber Costa MIME-Version: 1.0 Subject: Re: [PATCH] mm/memcg: add unlikely to mercg->move_charge_at_immigrate References: <1340025022-7272-1-git-send-email-liwp.linux@gmail.com> In-Reply-To: <1340025022-7272-1-git-send-email-liwp.linux@gmail.com> Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Wanpeng Li Cc: Johannes Weiner , Michal Hocko , Balbir Singh , KAMEZAWA Hiroyuki , cgroups@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Gavin Shan On 06/18/2012 05:10 PM, Wanpeng Li wrote: > From: Wanpeng Li > > move_charge_at_immigrate feature is disabled by default. Charges > are moved only when you move mm->owner and it also add additional > overhead. How big is this overhead? That's hardly a fast path. And if it happens to matter, it will be just bigger when you enable it, and the compiler start giving the wrong hints to the code. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751930Ab2FRNML (ORCPT ); Mon, 18 Jun 2012 09:12:11 -0400 Received: from mx2.parallels.com ([64.131.90.16]:47748 "EHLO mx2.parallels.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750915Ab2FRNMJ (ORCPT ); Mon, 18 Jun 2012 09:12:09 -0400 Message-ID: <4FDF2890.3020004@parallels.com> Date: Mon, 18 Jun 2012 17:09:36 +0400 From: Glauber Costa User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:13.0) Gecko/20120605 Thunderbird/13.0 MIME-Version: 1.0 To: Wanpeng Li CC: Johannes Weiner , Michal Hocko , Balbir Singh , KAMEZAWA Hiroyuki , , , , Gavin Shan Subject: Re: [PATCH] mm/memcg: add unlikely to mercg->move_charge_at_immigrate References: <1340025022-7272-1-git-send-email-liwp.linux@gmail.com> In-Reply-To: <1340025022-7272-1-git-send-email-liwp.linux@gmail.com> Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 06/18/2012 05:10 PM, Wanpeng Li wrote: > From: Wanpeng Li > > move_charge_at_immigrate feature is disabled by default. Charges > are moved only when you move mm->owner and it also add additional > overhead. How big is this overhead? That's hardly a fast path. And if it happens to matter, it will be just bigger when you enable it, and the compiler start giving the wrong hints to the code.