From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 62BDDC742A1 for ; Fri, 12 Jul 2019 01:04:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2B08A2084B for ; Fri, 12 Jul 2019 01:04:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1562893460; bh=Bo+q0hKf5LxeaSDApUoWhLNtI3MOCrePufeOx5LfW4Y=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=wsKgg+2sJgy3o4pnopp0uACWX6aJZDZks6ZxqX2ZHAPPj9fjyRspCaShhewZXKd0m ruNj4S9VXSnCfy0KEg1nySmPiKDH1dJ9cazz2gGShmX3iiIHYSJGyxhjh7Rg0UMfs2 tpK0RFc/FdYFwComC7S7MwAzfwyPmawyBQkN8y0w= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729002AbfGLBET (ORCPT ); Thu, 11 Jul 2019 21:04:19 -0400 Received: from mail.kernel.org ([198.145.29.99]:36938 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728102AbfGLBES (ORCPT ); Thu, 11 Jul 2019 21:04:18 -0400 Received: from localhost.localdomain (c-73-223-200-170.hsd1.ca.comcast.net [73.223.200.170]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 9C31E214AF; Fri, 12 Jul 2019 01:04:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1562893458; bh=Bo+q0hKf5LxeaSDApUoWhLNtI3MOCrePufeOx5LfW4Y=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=eIqKhpReC6BpOSmlhSKbSmEX+UF6UZwoQMoeeqZrA9bz5kt6Fa1wU4ocnSjH69X1g +yGG+J0opFVEOtIjbLclYHqZvjMxeT4i+rTawAiYusSoyp3wM8lN4VSx+dRY7HjOjp tvdun+s0YcfiReWs+eyaOs5n7rfM1HXSSVq6olg0= Date: Thu, 11 Jul 2019 18:04:17 -0700 From: Andrew Morton To: Vlastimil Babka Cc: Sai Charan Sane , mhocko@suse.com, tglx@linutronix.de, rppt@linux.vnet.ibm.com, gregkh@linuxfoundation.org, joe@perches.com, miles.chen@mediatek.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, a.sahrawat@samsung.com, pankaj.m@samsung.com, v.narang@samsung.com Subject: Re: [PATCH 1/1] mm/page_owner: store page_owner's gfp_mask in stackdepot itself Message-Id: <20190711180417.1358ba8b359f68bbf92cf3c2@linux-foundation.org> In-Reply-To: <24037235-2174-423f-9055-c6a49aa659e2@suse.cz> References: <1559886798-29585-1-git-send-email-s.charan@samsung.com> <24037235-2174-423f-9055-c6a49aa659e2@suse.cz> X-Mailer: Sylpheed 3.5.1 (GTK+ 2.24.31; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 17 Jun 2019 15:51:32 +0200 Vlastimil Babka wrote: > On 6/7/19 7:53 AM, Sai Charan Sane wrote: > > Memory overhead of 4MB is reduced by storing gfp_mask in stackdepot along > > with stacktrace. Stackdepot memory usage increased by ~100kb for 4GB of RAM. > > > > Page owner logs from dmesg: > > Before patch: > > allocated 20971520 bytes of page_ext > > After patch: > > allocated 16777216 bytes of page_ext > > > > Signed-off-by: Sai Charan Sane > > I don't know, this looks like unneeded abuse to me. In the debug > scenario when someone boots a kernel with page_owner enabled, does 4MB > out of 4GB RAM really make a difference? Thanks. I'll drop this patch.