Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754567Ab0KIVb4 (ORCPT ); Tue, 9 Nov 2010 16:31:56 -0500 Received: from smtp-out.google.com ([74.125.121.35]:6475 "EHLO smtp-out.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752749Ab0KIVbz (ORCPT ); Tue, 9 Nov 2010 16:31:55 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=google.com; s=beta; h=date:from:x-x-sender:to:cc:subject:in-reply-to:message-id :references:user-agent:mime-version:content-type; b=O9RnJOfiEw+mHYA6mYoFaoBbdv/Qw1P5NkWYGnyoLba5WXG4iHghAmnEKR3uBdGvaQ pDaMjvUTBbQ6CtfmBHAQ== Date: Tue, 9 Nov 2010 13:31:48 -0800 (PST) From: David Rientjes X-X-Sender: rientjes@chino.kir.corp.google.com To: Greg Thelen cc: Johannes Weiner , Andrew Morton , KAMEZAWA Hiroyuki , Balbir Singh , Daisuke Nishimura , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [patch] memcg: fix unit mismatch in memcg oom limit calculation In-Reply-To: Message-ID: References: <20101109110521.GS23393@cmpxchg.org> User-Agent: Alpine 2.00 (DEB 1167 2008-08-23) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-System-Of-Record: true Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1174 Lines: 30 On Tue, 9 Nov 2010, Greg Thelen wrote: > Johannes Weiner writes: > > > Adding the number of swap pages to the byte limit of a memory control > > group makes no sense. Convert the pages to bytes before adding them. > > > > The only user of this code is the OOM killer, and the way it is used > > means that the error results in a higher OOM badness value. Since the > > cgroup limit is the same for all tasks in the cgroup, the error should > > have no practical impact at the moment. > > > > But let's not wait for future or changing users to trip over it. > > Thanks for the fix. > > > Signed-off-by: Johannes Weiner > Reviewed-by: Greg Thelen > Nice catch, but it's done in the opposite way: the oom killer doesn't use byte limits but page limits. So this needs to be (res_counter_read_u64(&memcg->res, RES_LIMIT) >> PAGE_SHIFT) + total_swap_pages; -- 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/