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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED 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 97F90C4321D for ; Mon, 20 Aug 2018 01:21:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 403EA208C2 for ; Mon, 20 Aug 2018 01:21:42 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 403EA208C2 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=huawei.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726045AbeHTEfL (ORCPT ); Mon, 20 Aug 2018 00:35:11 -0400 Received: from szxga06-in.huawei.com ([45.249.212.32]:58371 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725931AbeHTEfK (ORCPT ); Mon, 20 Aug 2018 00:35:10 -0400 Received: from DGGEMS409-HUB.china.huawei.com (unknown [172.30.72.59]) by Forcepoint Email with ESMTP id 9A86EC0929168; Mon, 20 Aug 2018 09:21:35 +0800 (CST) Received: from [127.0.0.1] (10.134.22.195) by DGGEMS409-HUB.china.huawei.com (10.3.19.209) with Microsoft SMTP Server id 14.3.399.0; Mon, 20 Aug 2018 09:21:32 +0800 Subject: Re: [f2fs-dev] [PATCH v4] f2fs: fix performance issue observed with multi-thread sequential read To: Jaegeuk Kim , , References: <20180810023758.46974-1-jaegeuk@kernel.org> <20180810024859.GA48219@jaegeuk-macbookpro.roam.corp.google.com> <20180810185640.GA63079@jaegeuk-macbookpro.roam.corp.google.com> <20180817182944.GA58612@jaegeuk-macbookpro.roam.corp.google.com> From: Chao Yu Message-ID: <4899ff2c-5961-10e7-e074-af7442ceee15@huawei.com> Date: Mon, 20 Aug 2018 09:21:31 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <20180817182944.GA58612@jaegeuk-macbookpro.roam.corp.google.com> Content-Type: text/plain; charset="windows-1252" Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.134.22.195] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2018/8/18 2:29, Jaegeuk Kim wrote: > This reverts the commit - "b93f771 - f2fs: remove writepages lock" > to fix the drop in sequential read throughput. > > Test: ./tiotest -t 32 -d /data/tio_tmp -f 32 -b 524288 -k 1 -k 3 -L > device: UFS > > Before - > read throughput: 185 MB/s > total read requests: 85177 (of these ~80000 are 4KB size requests). > total write requests: 2546 (of these ~2208 requests are written in 512KB). > > After - > read throughput: 758 MB/s > total read requests: 2417 (of these ~2042 are 512KB reads). > total write requests: 2701 (of these ~2034 requests are written in 512KB). > > Signed-off-by: Sahitya Tummala > Signed-off-by: Jaegeuk Kim > --- > > Change log from v3: > - add more conditions to serialize the allocation > > Documentation/ABI/testing/sysfs-fs-f2fs | 8 ++++++++ > fs/f2fs/data.c | 10 ++++++++++ > fs/f2fs/f2fs.h | 2 ++ > fs/f2fs/segment.c | 1 + > fs/f2fs/super.c | 1 + > fs/f2fs/sysfs.c | 2 ++ > 6 files changed, 24 insertions(+) > > diff --git a/Documentation/ABI/testing/sysfs-fs-f2fs b/Documentation/ABI/testing/sysfs-fs-f2fs > index 9b0123388f18..94a24aedcdb2 100644 > --- a/Documentation/ABI/testing/sysfs-fs-f2fs > +++ b/Documentation/ABI/testing/sysfs-fs-f2fs > @@ -51,6 +51,14 @@ Description: > Controls the dirty page count condition for the in-place-update > policies. > > +What: /sys/fs/f2fs//min_seq_blocks > +Date: August 2018 > +Contact: "Jaegeuk Kim" > +Description: > + Controls the dirty page count condition for batched sequential > + writes in ->writepages. > + > + > What: /sys/fs/f2fs//min_hot_blocks > Date: March 2017 > Contact: "Jaegeuk Kim" > diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c > index 43d3723dc886..fb63425ea242 100644 > --- a/fs/f2fs/data.c > +++ b/fs/f2fs/data.c > @@ -2130,6 +2130,7 @@ static int __f2fs_write_data_pages(struct address_space *mapping, > struct f2fs_sb_info *sbi = F2FS_I_SB(inode); > struct blk_plug plug; > int ret; > + bool locked = false; > > /* deal with chardevs and other special file */ > if (!mapping->a_ops->writepage) > @@ -2160,10 +2161,19 @@ static int __f2fs_write_data_pages(struct address_space *mapping, > else if (atomic_read(&sbi->wb_sync_req[DATA])) > goto skip_write; > > + if (!S_ISDIR(inode->i_mode) && (wbc->sync_mode != WB_SYNC_ALL || > + get_dirty_pages(inode) <= SM_I(sbi)->min_seq_blocks)) { get_dirty_pages(inode) >= SM_I(sbi)->min_seq_blocks > + mutex_lock(&sbi->writepages); Still didn't see atomic write being covered by this lock. How about introducing a macro like __should_serialize_io() for indicating the condition in where we should serialize IOs. Thanks, > + locked = true; > + } > + > blk_start_plug(&plug); > ret = f2fs_write_cache_pages(mapping, wbc, io_type); > blk_finish_plug(&plug); > > + if (locked) > + mutex_unlock(&sbi->writepages); > + > if (wbc->sync_mode == WB_SYNC_ALL) > atomic_dec(&sbi->wb_sync_req[DATA]); > /* > diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h > index 9a6ba4a8d338..170573f8a04a 100644 > --- a/fs/f2fs/f2fs.h > +++ b/fs/f2fs/f2fs.h > @@ -913,6 +913,7 @@ struct f2fs_sm_info { > unsigned int ipu_policy; /* in-place-update policy */ > unsigned int min_ipu_util; /* in-place-update threshold */ > unsigned int min_fsync_blocks; /* threshold for fsync */ > + unsigned int min_seq_blocks; /* threshold for sequential blocks */ > unsigned int min_hot_blocks; /* threshold for hot block allocation */ > unsigned int min_ssr_sections; /* threshold to trigger SSR allocation */ > > @@ -1133,6 +1134,7 @@ struct f2fs_sb_info { > struct rw_semaphore sb_lock; /* lock for raw super block */ > int valid_super_block; /* valid super block no */ > unsigned long s_flag; /* flags for sbi */ > + struct mutex writepages; /* mutex for writepages() */ > > #ifdef CONFIG_BLK_DEV_ZONED > unsigned int blocks_per_blkz; /* F2FS blocks per zone */ > diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c > index b136e39e1e9e..20650e25117b 100644 > --- a/fs/f2fs/segment.c > +++ b/fs/f2fs/segment.c > @@ -4127,6 +4127,7 @@ int f2fs_build_segment_manager(struct f2fs_sb_info *sbi) > sm_info->ipu_policy = 1 << F2FS_IPU_FSYNC; > sm_info->min_ipu_util = DEF_MIN_IPU_UTIL; > sm_info->min_fsync_blocks = DEF_MIN_FSYNC_BLOCKS; > + sm_info->min_seq_blocks = sbi->blocks_per_seg * sbi->segs_per_sec; > sm_info->min_hot_blocks = DEF_MIN_HOT_BLOCKS; > sm_info->min_ssr_sections = reserved_sections(sbi); > > diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c > index c6e4750a9187..6b6cb4eb8439 100644 > --- a/fs/f2fs/super.c > +++ b/fs/f2fs/super.c > @@ -2864,6 +2864,7 @@ static int f2fs_fill_super(struct super_block *sb, void *data, int silent) > /* init f2fs-specific super block info */ > sbi->valid_super_block = valid_super_block; > mutex_init(&sbi->gc_mutex); > + mutex_init(&sbi->writepages); > mutex_init(&sbi->cp_mutex); > init_rwsem(&sbi->node_write); > init_rwsem(&sbi->node_change); > diff --git a/fs/f2fs/sysfs.c b/fs/f2fs/sysfs.c > index cd2e030e47b8..81c0e5337443 100644 > --- a/fs/f2fs/sysfs.c > +++ b/fs/f2fs/sysfs.c > @@ -397,6 +397,7 @@ F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, batched_trim_sections, trim_sections); > F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, ipu_policy, ipu_policy); > F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, min_ipu_util, min_ipu_util); > F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, min_fsync_blocks, min_fsync_blocks); > +F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, min_seq_blocks, min_seq_blocks); > F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, min_hot_blocks, min_hot_blocks); > F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, min_ssr_sections, min_ssr_sections); > F2FS_RW_ATTR(NM_INFO, f2fs_nm_info, ram_thresh, ram_thresh); > @@ -449,6 +450,7 @@ static struct attribute *f2fs_attrs[] = { > ATTR_LIST(ipu_policy), > ATTR_LIST(min_ipu_util), > ATTR_LIST(min_fsync_blocks), > + ATTR_LIST(min_seq_blocks), > ATTR_LIST(min_hot_blocks), > ATTR_LIST(min_ssr_sections), > ATTR_LIST(max_victim_search), >