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=-3.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED 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 92680C55178 for ; Fri, 30 Oct 2020 15:46:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F41E922242 for ; Fri, 30 Oct 2020 15:46:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="key not found in DNS" (0-bit key) header.d=szeredi.hu header.i=@szeredi.hu header.b="FgyeQX4a" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726674AbgJ3PqN (ORCPT ); Fri, 30 Oct 2020 11:46:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46678 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726319AbgJ3PqN (ORCPT ); Fri, 30 Oct 2020 11:46:13 -0400 Received: from mail-vs1-xe44.google.com (mail-vs1-xe44.google.com [IPv6:2607:f8b0:4864:20::e44]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 59930C0613CF for ; Fri, 30 Oct 2020 08:46:13 -0700 (PDT) Received: by mail-vs1-xe44.google.com with SMTP id h5so3648741vsp.3 for ; Fri, 30 Oct 2020 08:46:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=szeredi.hu; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=CFcH78Yw0pfxvt3AwM9fYeXCITwB39A7gKKajxur5/0=; b=FgyeQX4aoiBbFM79EBFleLczgQbrNa2HsouqPxpbgexC5/AI1Hhd5zzIZYFgf8IXUq pAarAosw+OfibouTp7RrVPFobobEau7rYvSuJ1vXunTL1MR/t8IAzrEKkDFq+0vTNGYT 9B6R2nxmqxrZqXn2SfZi2FTHBFfQwSWjiqKOQ= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=CFcH78Yw0pfxvt3AwM9fYeXCITwB39A7gKKajxur5/0=; b=G/5PhtIn6Esm9fK1lpS3rSBu0NSNabcMuVzsTea2zC8Uio3ew/OD2TxzmgTmf2+zPi PuXJANSqZ3hF38J2aSSLnYJ7AM6vweFQYxMi9R0ynZhH6FWBhf+sPswtYtja1288bNKt JxUvI/QAqcgxCPZxO75wDsLjxWLYJEa2X7sO8NtyLAYiiQqF9pSKWhXmUqCgvc/M6Fcp 5RAY8NFA+0sPFL/wKPpZUKrKsWFAK+8dptWFF1fcibqczhwWDCxEfgO3JyUs5sMz26Ik ecjXtchK7QoNnkeYevfzT7/v0HnBDT3ECtFy7dUhHm+qx5kCeSl31bgD9UFNaXllCk2P KZBw== X-Gm-Message-State: AOAM533L19GjNFVNbd7qO6egQ7qna5/aP6OtLi4F8TFtC7QqKOKnWYEx ME+683XRYQPY9RdfgsYfu2fzUKFBl4dnsatz5mAJPw== X-Google-Smtp-Source: ABdhPJzgkbkcDlD/QWNYdVwGIN85FgPiKqcrWoajHn+aHB4z4aaAgVMPRcxnlcxrnWFoVc15DrfrayMXQxD31PHZfT8= X-Received: by 2002:a05:6102:2ec:: with SMTP id j12mr7559124vsj.21.1604072772593; Fri, 30 Oct 2020 08:46:12 -0700 (PDT) MIME-Version: 1.0 References: <20201025034117.4918-1-cgxu519@mykernel.net> In-Reply-To: <20201025034117.4918-1-cgxu519@mykernel.net> From: Miklos Szeredi Date: Fri, 30 Oct 2020 16:46:00 +0100 Message-ID: Subject: Re: [RFC PATCH v2 0/8] implement containerized syncfs for overlayfs To: Chengguang Xu Cc: Amir Goldstein , Jan Kara , overlayfs , linux-fsdevel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-unionfs@vger.kernel.org On Sun, Oct 25, 2020 at 4:42 AM Chengguang Xu wrote: > > Current syncfs(2) syscall on overlayfs just calls sync_filesystem() > on upper_sb to synchronize whole dirty inodes in upper filesystem > regardless of the overlay ownership of the inode. In the use case of > container, when multiple containers using the same underlying upper > filesystem, it has some shortcomings as below. > > (1) Performance > Synchronization is probably heavy because it actually syncs unnecessary > inodes for target overlayfs. > > (2) Interference > Unplanned synchronization will probably impact IO performance of > unrelated container processes on the other overlayfs. > > This series try to implement containerized syncfs for overlayfs so that > only sync target dirty upper inodes which are belong to specific overlayfs > instance. By doing this, it is able to reduce cost of synchronization and > will not seriously impact IO performance of unrelated processes. Series looks good at first glance. Still need to do an in-depth review. In the meantime can you post some numbers showing the performance improvements? Thanks, Miklos