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 A3EBDC433EF for ; Thu, 26 May 2022 14:47:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245267AbiEZOrO (ORCPT ); Thu, 26 May 2022 10:47:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45802 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1347736AbiEZOrL (ORCPT ); Thu, 26 May 2022 10:47:11 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4CF1220BCC for ; Thu, 26 May 2022 07:47:07 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id CFFD5B820F8 for ; Thu, 26 May 2022 14:47:05 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C6E6FC385A9; Thu, 26 May 2022 14:47:03 +0000 (UTC) Authentication-Results: smtp.kernel.org; dkim=pass (1024-bit key) header.d=zx2c4.com header.i=@zx2c4.com header.b="bR5QieuF" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=zx2c4.com; s=20210105; t=1653576422; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=qlg0D7t6m5vNAARZb66/P3VDfiBplW1kc1c3tetuqvg=; b=bR5QieuF3jlsgoECQGnm07qptNbWLM21ZFebRW1bdk+QLO/tF8j/n37mMKZNj6jWqik3sv WPYzSxghhBQzYitbolGbTsE2xuUxvUJqE0rj99qgl7a4XxycV/7gwYAlBtR79XhH9bUhxP SfS8wa2VSKnQXPWJFcCZP6Ch8twyBJI= Received: by mail.zx2c4.com (ZX2C4 Mail Server) with ESMTPSA id 19c32fa6 (TLSv1.3:AEAD-AES256-GCM-SHA384:256:NO); Thu, 26 May 2022 14:47:01 +0000 (UTC) Date: Thu, 26 May 2022 16:46:56 +0200 From: "Jason A. Donenfeld" To: Jens Axboe Cc: 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: <9c3a6ad4-cdb5-8e0d-9b01-c2825ea891ad@kernel.dk> <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=utf-8 Content-Disposition: inline In-Reply-To: <2ae13aa9-f180-0c71-55db-922c0f18dc1b@kernel.dk> Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org 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... Jason