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=-18.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 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 31E38C4338F for ; Fri, 13 Aug 2021 01:14:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 049B160295 for ; Fri, 13 Aug 2021 01:14:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238094AbhHMBO3 (ORCPT ); Thu, 12 Aug 2021 21:14:29 -0400 Received: from mail.kernel.org ([198.145.29.99]:48778 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233641AbhHMBO2 (ORCPT ); Thu, 12 Aug 2021 21:14:28 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 3214160FBF; Fri, 13 Aug 2021 01:14:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1628817242; bh=oqWfN9ilzD/7n0LwaQHtvqSaNRECuSXyIM9UHWrUZdc=; h=Subject:To:Cc:References:From:Date:In-Reply-To:From; b=CdBx6G47/FOs/EVueNi01CWLNDrJCZMOZc1oMJ+jKka9mFHYre9ZbZvsVStfllaea 5DxHGLZI2jfRAxCwEP69l390e4MwmpbstP35UX4L0aLu2GTBgo52INEtOdXqBfldUe t6Sr/tkOiEuZTH5QBVgWaLJbTwYMvgoc2fGC0xtdgT3tUs4gmw/hGEZ+vyTlN4a7Nu Bqa/TNtW6GwK3d86QVipjnIQelUhdpgkXqcpWB04JMkYoKMqM0ZN5VhJZeukytCJK8 u1Lff6+PY02eZyVwdTGcZ+FV1fT8AXId9LB7s6YEPgvrXy+RA8DQC7A/Z1h4iMMYkw uuW8LP8DPv9vg== Subject: Re: [f2fs-dev] [PATCH v2] f2fs: introduce periodic iostat io latency traces To: Jaegeuk Kim Cc: Daeho Jeong , linux-kernel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, kernel-team@android.com, Daeho Jeong References: <20210803225542.3487172-1-daeho43@gmail.com> <2a79c1c5-366b-92d9-4025-dbda660b1178@kernel.org> From: Chao Yu Message-ID: Date: Fri, 13 Aug 2021 09:14:00 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.12.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2021/8/13 4:52, Jaegeuk Kim wrote: > On 08/11, Chao Yu wrote: >> Hi Daeho, >> >> On 2021/8/4 6:55, Daeho Jeong wrote: >>> From: Daeho Jeong >>> >>> Whenever we notice some sluggish issues on our machines, we are always >>> curious about how well all types of I/O in the f2fs filesystem are >>> handled. But, it's hard to get this kind of real data. First of all, >>> we need to reproduce the issue while turning on the profiling tool like >>> blktrace, but the issue doesn't happen again easily. Second, with the >>> intervention of any tools, the overall timing of the issue will be >>> slightly changed and it sometimes makes us hard to figure it out. >>> >>> So, I added F2FS_IOSTAT_IO_LATENCY config option to support printing out >>> IO latency statistics tracepoint events which are minimal things to >>> understand filesystem's I/O related behaviors. With "iostat_enable" sysfs >>> node on, we can get this statistics info in a periodic way and it >>> would cause the least overhead. >>> >>> [samples] >>> f2fs_ckpt-254:1-507 [003] .... 2842.439683: f2fs_iostat_latency: >>> dev = (254,11), iotype [peak lat.(ms)/avg lat.(ms)/count], >>> rd_data [136/1/801], rd_node [136/1/1704], rd_meta [4/2/4], >>> wr_sync_data [164/16/3331], wr_sync_node [152/3/648], >>> wr_sync_meta [160/2/4243], wr_async_data [24/13/15], >>> wr_async_node [0/0/0], wr_async_meta [0/0/0] >>> >>> f2fs_ckpt-254:1-507 [002] .... 2845.450514: f2fs_iostat_latency: >>> dev = (254,11), iotype [peak lat.(ms)/avg lat.(ms)/count], >>> rd_data [60/3/456], rd_node [60/3/1258], rd_meta [0/0/1], >>> wr_sync_data [120/12/2285], wr_sync_node [88/5/428], >>> wr_sync_meta [52/6/2990], wr_async_data [4/1/3], >>> wr_async_node [0/0/0], wr_async_meta [0/0/0] >>> >>> Signed-off-by: Daeho Jeong >>> >>> --- >>> v2: clean up with wrappers and fix a build breakage reported by >>> kernel test robot >>> --- >>> fs/f2fs/Kconfig | 9 +++ >> >> I try to apply this patch in my local dev branch, but it failed due to >> conflicting with below commit, it needs to rebase this patch to last dev >> branch. > > I applied this in dev branch. Could you please check? Yeah, I see. >>> +config F2FS_IOSTAT_IO_LATENCY >>> + bool "F2FS IO statistics IO latency information" >>> + depends on F2FS_FS >>> + default n >>> + help >>> + Support printing out periodic IO latency statistics tracepoint >>> + events. With this, you have to turn on "iostat_enable" sysfs >>> + node to print this out. >> >> This functionality looks independent, how about introuducing iostat.h >> and iostat.c (not sure, maybe trace.[hc])to include newly added structure >> and functions for dispersive codes cleanup. Thoughts? this also can avoid using CONFIG_F2FS_IOSTAT_IO_LATENCY in many places. Thanks,