From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.1 (2015-04-28) on archive.lwn.net X-Spam-Level: X-Spam-Status: No, score=-5.8 required=5.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham autolearn_force=no version=3.4.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by archive.lwn.net (Postfix) with ESMTP id E7F5A7D043 for ; Sat, 30 Jun 2018 02:41:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S936540AbeF3ClW (ORCPT ); Fri, 29 Jun 2018 22:41:22 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:60594 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S936522AbeF3ClU (ORCPT ); Fri, 29 Jun 2018 22:41:20 -0400 Received: from localhost.localdomain (c-24-4-125-7.hsd1.ca.comcast.net [24.4.125.7]) by mail.linuxfoundation.org (Postfix) with ESMTPSA id D67C6AF3; Sat, 30 Jun 2018 02:41:18 +0000 (UTC) Date: Fri, 29 Jun 2018 19:41:17 -0700 From: Andrew Morton To: Andrey Konovalov Cc: Andrey Ryabinin , Alexander Potapenko , Dmitry Vyukov , Catalin Marinas , Will Deacon , Christoph Lameter , Mark Rutland , Nick Desaulniers , Marc Zyngier , Dave Martin , Ard Biesheuvel , "Eric W . Biederman" , Ingo Molnar , Paul Lawrence , Geert Uytterhoeven , Arnd Bergmann , "Kirill A . Shutemov" , Greg Kroah-Hartman , Kate Stewart , Mike Rapoport , kasan-dev , linux-doc@vger.kernel.org, LKML , Linux ARM , linux-sparse@vger.kernel.org, Linux Memory Management List , Linux Kbuild mailing list , Kostya Serebryany , Evgeniy Stepanov , Lee Smith , Ramana Radhakrishnan , Jacob Bramley , Ruben Ayrapetyan , Jann Horn , Mark Brand , Chintan Pandya Subject: Re: [PATCH v4 00/17] khwasan: kernel hardware assisted address sanitizer Message-Id: <20180629194117.01b2d31e805808eee5c97b4d@linux-foundation.org> In-Reply-To: References: <20180627160800.3dc7f9ee41c0badbf7342520@linux-foundation.org> <20180628124039.8a42ab5e2994fb2876ff4f75@linux-foundation.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 Sender: linux-doc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org On Fri, 29 Jun 2018 14:45:08 +0200 Andrey Konovalov wrote: > >> What kind of memory consumption testing would you like to see? > > > > Well, 100kb or so is a teeny amount on virtually any machine. I'm > > assuming the savings are (much) more significant once the machine gets > > loaded up and doing work? > > So with clean kernel after boot we get 40 kb memory usage. With KASAN > it is ~120 kb, which is 200% overhead. With KHWASAN it's 50 kb, which > is 25% overhead. This should approximately scale to any amounts of > used slab memory. For example with 100 mb memory usage we would get > +200 mb for KASAN and +25 mb with KHWASAN. (And KASAN also requires > quarantine for better use-after-free detection). I can explicitly > mention the overhead in %s in the changelog. > > If you think it makes sense, I can also make separate measurements > with some workload. What kind of workload should I use? Whatever workload people were running when they encountered problems with KASAN memory consumption ;) I dunno, something simple. `find / > /dev/null'? -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html