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=-2.2 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 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 4A6F9C43331 for ; Thu, 26 Mar 2020 16:47:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1F1262073E for ; Thu, 26 Mar 2020 16:47:48 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=malat-biz.20150623.gappssmtp.com header.i=@malat-biz.20150623.gappssmtp.com header.b="GIr3jiVd" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727443AbgCZQrr (ORCPT ); Thu, 26 Mar 2020 12:47:47 -0400 Received: from mail-wr1-f65.google.com ([209.85.221.65]:45408 "EHLO mail-wr1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726163AbgCZQrq (ORCPT ); Thu, 26 Mar 2020 12:47:46 -0400 Received: by mail-wr1-f65.google.com with SMTP id t7so8607995wrw.12 for ; Thu, 26 Mar 2020 09:47:44 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=malat-biz.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=kYmZ7W7spXJCoSjpaQQC+a9kzIPwWZNW6wR0y26VyYE=; b=GIr3jiVdrqj3bn59MVLn4TI9NEimaDRJDtviwTb1yGhBa4MRpNqFrbqzMF1fYfGVyo zyjFWXtmLjvyFM+kTu2YAvkZCtbSAZ/SpplHv2w7uu3gpFdPI3hOY3FlpoVSJooIiuS2 rgN04v4rRUDOgRrktidIM0Dxy9Jbe0qXePkvXL2Oz3dTVTT5ya2XFOsaxZZ0D1N9rFaz b+5CKnM4F5wcg2ovEo5pLcgNAuvq2RydWfGPN26aWoYYA72NoHbBVWJRY+9ZOVOho4uj td34p19/XoQpGn8MFPanfE+Ke1/KARSmsW3CUfSFAbRg8xFvHbRjIND5iX4+KvJ0k6qV 9o9A== 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=kYmZ7W7spXJCoSjpaQQC+a9kzIPwWZNW6wR0y26VyYE=; b=GPoU7AAN+dV8sHsbSAosT0mZq1D+UQ2gFtKj39mdFkfufZoN3ugo5aIWKkuiJ4tGgH mSqR8VQpZ5JkgRBXPgc3XGQN3QaeSbzxb8RuuBke9I4py9U8oSPsXgIzPpJQanIfuDXZ 0ZeUhvdTjmUyR5cwEGN58YB1FTZvuERcBOA9dqE2GWvxwHPDvUtBjxArzM2rnMDoslfA nrXi5KBazPZsWSM8ad9wQl/FrDIxpN+L+3xn1NpQPuJSg69jLw2ucN/YLPxfHqmHVYju yRPYdPPR2sRf/nF8I9I6D7hIZL+9UdIhR6XyMBnHTGoJuk3GOH85Xx1puDLhY007QSF6 JIDQ== X-Gm-Message-State: ANhLgQ228m/Z+nV/IOrxDTA+kApmCuziSDoyeImMjrUxfFFRVTxYPPkl SHmzSkvnUwPm+tzGklPzcF2JHw== X-Google-Smtp-Source: ADFU+vuRzdEN8e+GgVOpVQoXZAfKd/+Jvd09vBvkB4h9XjIMrTsmDS1awfgMR59e60AKC7QqAgFC2w== X-Received: by 2002:adf:f104:: with SMTP id r4mr9875048wro.375.1585241263872; Thu, 26 Mar 2020 09:47:43 -0700 (PDT) Received: from ntb.petris.klfree.czf (p5B36386E.dip0.t-ipconnect.de. [91.54.56.110]) by smtp.gmail.com with ESMTPSA id e5sm4130732wru.92.2020.03.26.09.47.42 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 26 Mar 2020 09:47:43 -0700 (PDT) Date: Thu, 26 Mar 2020 17:47:32 +0100 From: Petr Malat To: Nick Terrell Cc: Nick Terrell , linux-kernel@vger.kernel.org, Chris Mason , linux-kbuild@vger.kernel.org, x86@kernel.org, gregkh@linuxfoundation.org, Kees Cook , Kernel Team , Adam Borowski , Patrick Williams , rmikey@fb.com, mingo@kernel.org, Patrick Williams Subject: Re: [PATCH v3 3/8] lib: add zstd support to decompress Message-ID: <20200326164732.GA17157@ntb.petris.klfree.czf> References: <20200325195849.407900-1-nickrterrell@gmail.com> <20200325195849.407900-4-nickrterrell@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200325195849.407900-4-nickrterrell@gmail.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi! On Wed, Mar 25, 2020 at 12:58:44PM -0700, Nick Terrell wrote: > From: Nick Terrell > * Add unzstd() and the zstd decompress interface. Here I do not understand why you limit the window size to 8MB even when you read a larger value from the header. I do not see a reason why there should be such a limitation at the first place and if there should be, why it differs from ZSTD_WINDOWLOG_MAX. I removed that limitation to be able to test it in my environment and I found the performance is worst than with my patch by roughly 20% (on i7-3520M), which is a major drawback considering the main motivation to use zstd is the decompression speed. I will test on arm as well and share the result tomorrow. Petr