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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 88C32C433F5 for ; Fri, 27 May 2022 10:09:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237394AbiE0KJu (ORCPT ); Fri, 27 May 2022 06:09:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42542 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240588AbiE0KJt (ORCPT ); Fri, 27 May 2022 06:09:49 -0400 Received: from mail-ed1-x52b.google.com (mail-ed1-x52b.google.com [IPv6:2a00:1450:4864:20::52b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 382C11271AE for ; Fri, 27 May 2022 03:09:48 -0700 (PDT) Received: by mail-ed1-x52b.google.com with SMTP id g20so4803540edj.10 for ; Fri, 27 May 2022 03:09:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=kxPnNMX0kfNK6RZbtSAzMK61GhUb48rVr91aOjS8Jjc=; b=h5W7HRgSZNk8u8hbAiuGGYO10XuAvVBiFkq2Gxujroxf31neQT2/IL6g5CJMVwE8IQ 7KhsJVaWKNA7k1BtIGki4RP1HVauP6t8l0030grKhUP2PW3wABSRitieIXLD6yzRG2ZS /h2yqqCQ4/DjY7olA/t6oFBHSywNfXVubG0hVLTJoFn4LFZQ0TV2QwrFCOIKQwIvtL/h mc8UBWTZtiq+cvEbxaCJHLYNj3lhJi3mTQnTOLtFkyn6ZKL53+9UZR7uRWCurrIluYHk u3yQGotWq+fw1RDk5F4GWWlE4erx+u93BZmbhBULeqWyZnGIbEQ5Bef5j0VRRmOZBsB6 UvQQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to; bh=kxPnNMX0kfNK6RZbtSAzMK61GhUb48rVr91aOjS8Jjc=; b=gzbJZefe2uTEPKkjRs11iNxMMuvV1N9AilWtYf7YUV32/NtwUNLkjdFsNKOAbnrnNl UG41G/Xmnr68beGi1mobj/xyEm6boTXdr5oinsvGMgnJlJq26ITlw1XhSkSwqajsx//A IoLAxlXH4s+nIXZ2RhX0ZWpqp9s5K/Glls33RcrIsazZPIWIxweeAB8uvPSLyf5afr7n qaubN+81o6vhFH1XTpfm1usvEwiqo3mRoYzJ+Zyix2ZGRVWVm/M4CSRqyuCyf4fMDTVx 7OGrr22hVNRVhaDVO4ychfgPl2iBaEeRIRFPYa8BlOuDHKblLeA7zOgKwmpRGNEiYmMl kvow== X-Gm-Message-State: AOAM533Yabx6TjUUrVc38B0XcKz+h2v0Y7QaqZRzfYZt3vTB3TX6EO2v +8zZcRRM0Cqt/Dbb86NxJ7A= X-Google-Smtp-Source: ABdhPJzsV+fjW8ANeSPoG4PYCg6JwNCJK/usm8tOpV0eq/aG89ade6LjbxyBEwEVgIngM0jJPVJ0XQ== X-Received: by 2002:a05:6402:ea1:b0:42b:2c59:503 with SMTP id h33-20020a0564020ea100b0042b2c590503mr36277449eda.9.1653646186813; Fri, 27 May 2022 03:09:46 -0700 (PDT) Received: from gmail.com (563BA16F.dsl.pool.telekom.hu. [86.59.161.111]) by smtp.gmail.com with ESMTPSA id cd26-20020a170906b35a00b006fee526ed72sm1297847ejb.217.2022.05.27.03.09.45 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 27 May 2022 03:09:46 -0700 (PDT) Sender: Ingo Molnar Date: Fri, 27 May 2022 12:09:44 +0200 From: Ingo Molnar To: "Jason A. Donenfeld" , Samuel Neves Cc: Jens Axboe , Matthew Wilcox , Al Viro , Christoph Hellwig , linux-fsdevel@vger.kernel.org, x86@kernel.org Subject: Re: [RFC] what to do with IOCB_DSYNC? Message-ID: References: <6ea33ba8-c5a3-a1e7-92d2-da8744662ed9@kernel.dk> <0343869c-c6d1-5e7c-3bcb-f8d6999a2e04@kernel.dk> <6594c360-0c7c-412f-29c9-377ddda16937@kernel.dk> <2ae13aa9-f180-0c71-55db-922c0f18dc1b@kernel.dk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org * Jason A. Donenfeld wrote: > On Mon, May 23, 2022 at 10:03:45AM -0600, Jens Axboe wrote: > > clear_user() > > 32 ~96MB/sec > > 64 195MB/sec > > 128 386MB/sec > > 1k 2.7GB/sec > > 4k 7.8GB/sec > > 16k 14.8GB/sec > > > > copy_from_zero_page() > > 32 ~96MB/sec > > 64 193MB/sec > > 128 383MB/sec > > 1k 2.9GB/sec > > 4k 9.8GB/sec > > 16k 21.8GB/sec > > Just FYI, on x86, Samuel Neves proposed some nice clear_user() > performance improvements that were forgotten about: > > https://lore.kernel.org/lkml/20210523180423.108087-1-sneves@dei.uc.pt/ > https://lore.kernel.org/lkml/Yk9yBcj78mpXOOLL@zx2c4.com/ > > Hoping somebody picks this up at some point... Those ~2x speedup numbers are indeed looking very nice: | After this patch, on a Skylake CPU, these are the | before/after figures: | | $ dd if=/dev/zero of=/dev/null bs=1024k status=progress | 94402248704 bytes (94 GB, 88 GiB) copied, 6 s, 15.7 GB/s | | $ dd if=/dev/zero of=/dev/null bs=1024k status=progress | 446476320768 bytes (446 GB, 416 GiB) copied, 15 s, 29.8 GB/s Patch fell through the cracks & it doesn't apply anymore: checking file arch/x86/lib/usercopy_64.c Hunk #2 FAILED at 17. 1 out of 2 hunks FAILED Would be nice to re-send it. Thanks, Ingo