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=-2.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=ham 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 BFE16C43441 for ; Thu, 29 Nov 2018 04:46:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 69A982081C for ; Thu, 29 Nov 2018 04:46:51 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="eBHCV+dF" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 69A982081C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727666AbeK2PuM (ORCPT ); Thu, 29 Nov 2018 10:50:12 -0500 Received: from mail-pf1-f196.google.com ([209.85.210.196]:39277 "EHLO mail-pf1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727327AbeK2PuM (ORCPT ); Thu, 29 Nov 2018 10:50:12 -0500 Received: by mail-pf1-f196.google.com with SMTP id c72so397581pfc.6 for ; Wed, 28 Nov 2018 20:46:11 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=/R74h8rp78HGLdw2BWKROW5d8ewk9KsmzZ8gDi4rZyY=; b=eBHCV+dFXATz8mdv6TqJ97LFjzJLg7rAl+0bZj2Y2d9rDQpyjRaOGsz+ZboXrb5ITI PSLmVEvOcYyy9P78j2ufTApVxMgMV1vriUgoioGWe2dvikIHIPTfA5GfJGaHu1TjVHjl QgCVO4rYCqlrUpXGB2l1jHb4SCkmsZtFNdcTJMdNP2tKNIHuVSnhnktLu1IYwqZwycFT nqDfd7h2WjrfzDCJpPK/gtZo2PkjLdEum3p94e/l0s05gI7V1nPp8gd6HLz5AQjAe5vm SenH5hjt6eqb8isY9CaBSx/s/ef5Pb2Ho1NCvGotPUy2UwqqEUTsAFm541L/hN928fbH 5QgA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=/R74h8rp78HGLdw2BWKROW5d8ewk9KsmzZ8gDi4rZyY=; b=Xj8Y7FweBzrczoHEELcalQbdnO0uVgd+wOybAwXgLNFY7wkSajDJMBrnfrKeZres8O VecVO3t88x2TqECOatsRkoqppNh2DupwoYzi3ccFeYciMCqPR8XEzXKepk2ZoCPSyckS WtIupN4Ivx26GshTNgS9+7Iqgu19dSNnGlqg5AIxO3Zrk/4nZRXINK7TFYVyU1QLckzJ i0igvKH3+HuCTeGn/vCGCuQ5QuTW7HESHHK5PoQjtdUr0hCkL+ofKqeuaq/8Icr1CfC4 qnPGbKCDT5Sbo5G8kmMagI8bkOcuqr2y7mtfc/jfnNowZyvI0OLnTEwM4QhyXxBbwpcm QOYA== X-Gm-Message-State: AA+aEWZrkkNMM96/in38s+zw5zSPDioYJIgahfSIdtmfm8zxnIGDNUo3 OpJHfeaC8Jh3gdqmOTS+SA2P/JKR X-Google-Smtp-Source: AFSGD/XJ6r5toV3fbwPBevAnIJ3fvBVH9pAB1mqBk3b7/jJXZQcqn0B+XLkdlaf+ipjMxR2wcIIJTQ== X-Received: by 2002:a65:5a8e:: with SMTP id c14mr15390pgt.137.1543466770745; Wed, 28 Nov 2018 20:46:10 -0800 (PST) Received: from localhost ([175.223.15.27]) by smtp.gmail.com with ESMTPSA id v76sm950544pfj.145.2018.11.28.20.46.09 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Wed, 28 Nov 2018 20:46:09 -0800 (PST) Date: Thu, 29 Nov 2018 13:46:06 +0900 From: Sergey Senozhatsky To: Dave Rodgman Cc: "linux-kernel@vger.kernel.org" , nd , "herbert@gondor.apana.org.au" , "davem@davemloft.net" , Matt Sealey , "nitingupta910@gmail.com" , "rpurdie@openedhand.com" , "markus@oberhumer.com" , "minchan@kernel.org" , "sergey.senozhatsky.work@gmail.com" , "sonnyrao@google.com" , "gregkh@linuxfoundation.org" , "akpm@linux-foundation.org" Subject: Re: [PATCH v2 0/7] lib/lzo: performance improvements Message-ID: <20181129044606.GI6379@jagdpanzerIV> References: <20181127161913.23863-1-dave.rodgman@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181127161913.23863-1-dave.rodgman@arm.com> User-Agent: Mutt/1.11.0 (2018-11-25) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On (11/27/18 16:19), Dave Rodgman wrote: > > Right. The number is data dependent. Not all swapped out pages can be > > compressed; compressed pages that end up being >= zs_huge_class_size() are > > considered incompressible and stored as it. > > > > I'd say that on my setups around 50-60% of pages are incompressible. > > So, just to give a bit more detail: the test setup was a Samsung > Chromebook Pro, cycling through 80 tabs in Chrome. With lzo-rle, only > 5% of pages increased in size, and 90% of pages compress to 75% of > original size (or better). Mean compression ratio was 41%. Importantly > for lzo-rle, there are a lot of low-entropy pages where it can do well: > in total about 20% of the data is zeros forming part of a run of 4 or > more bytes. > > As a quick summary of the impact of these patches on bigger chunks of > data, I've compared the performance of four different variants of lzo > on two large (~40 MB) files. The numbers show round-trip throughput > in MB/s: > > Variant | Low-entropy | High-entropy > Current lzo | 242 | 157 > Arm opts | 290 | 159 > RLE | 876 | 151 > Arm opts + RLE | 1150 | 181 > > So both the Arm optimisations (8,16-byte copy & CTZ patches), and the > RLE implementation make a significant contribution to the overall > performance uplift. Cool! -ss