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=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, NICE_REPLY_A,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 030EEC2D0E4 for ; Thu, 12 Nov 2020 22:57:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7C59B20A8B for ; Thu, 12 Nov 2020 22:57:11 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="ydfDKZRo" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727021AbgKLW5K (ORCPT ); Thu, 12 Nov 2020 17:57:10 -0500 Received: from mail.kernel.org ([198.145.29.99]:50692 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726611AbgKLW5K (ORCPT ); Thu, 12 Nov 2020 17:57:10 -0500 Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (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 80B1C20872; Thu, 12 Nov 2020 22:56:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1605221811; bh=qyrksHKsDkON9A2dFh/FzxMGbEbdaxKiptmd9uwhFpQ=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=ydfDKZRoTdcGhT8pZExOdxMueL888zbl3NizoJH4yLQf9340UTy2ShCMV74dYist9 sGvAYW5RMq+nyQ3d9Pzt/YdChvaHcctBj7WmE6B3KpLmNJNMQVhf9UZvrjq3jfMnJR +KX0QnTPyihu5GQt30d5bLOUuVCDIZIPgr59H/g0= Date: Thu, 12 Nov 2020 14:56:49 -0800 From: Andrew Morton To: Vijayanand Jitta Cc: Minchan Kim , linux-mm , glider@google.com, Dan Williams , broonie@kernel.org, mhiramat@kernel.org, "linux-kernel@vger.kernel.org" , Yogesh Lal , Vinayak Menon Subject: Re: [PATCH] lib: stackdepot: Add support to configure STACK_HASH_SIZE Message-Id: <20201112145649.3fcd9dc4d6d3db4bd26245bb@linux-foundation.org> In-Reply-To: References: <1603372546-27118-1-git-send-email-vjitta@codeaurora.org> <282d7028-498d-50b3-37d4-2381571f9f9e@codeaurora.org> 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 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 12 Nov 2020 18:26:24 +0530 Vijayanand Jitta wrote: > >> 1. page_owner=off, stackdepot_stack_hash=0 -> no more wasted memory > >> when we don't use page_owner > >> 2. page_owner=on, stackdepot_stack_hash=8M -> reasonable hash size > >> when we use page_owner. > >> > >> > > > > This idea looks fine to me. Andrew and others would like to hear your > > comments as well on this before implementing. > > > > Thanks, > > Vijay > > > > Awaiting for comments from Andrew and others. I don't actually understand the problem. What is it about page-owner that causes stackdepot to consume additional memory? As far as I can tell, sizeof(struct stack_record) isn't affected by page-owner?