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 700F7C433EF for ; Tue, 15 Mar 2022 11:46:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242461AbiCOLsJ (ORCPT ); Tue, 15 Mar 2022 07:48:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33356 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1343754AbiCOLsI (ORCPT ); Tue, 15 Mar 2022 07:48:08 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 053DB5005A for ; Tue, 15 Mar 2022 04:46:57 -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 dfw.source.kernel.org (Postfix) with ESMTPS id E3F36614C6 for ; Tue, 15 Mar 2022 11:46:48 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E9AEDC340E8; Tue, 15 Mar 2022 11:46:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1647344808; bh=/cPGSXo6SCLZCEsU+UTNLu0PeAz0rnaMFL2HPm/XxUI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=cYb2iWpBjNyMkdPYsQtM/Gcu1vRZS7LLdeHMpCc5CKcpPjLFVS1D33OH8jdQpRi5X 9nNvjoD8Ax54wF+YPv0JGQielFRzFw9YtduXsftJRxSAzJFDAdHYfwAmX6suLXR7iF F80V8eLIY7+De3ISoHw29C3gWF6JpqBPJ409/gMd+Hzz4LrPUwEnK9bpOUmQJ7J6x0 EfL0eQZa55fcdyTcptGaRxwZKdaTaRcBNvhy8SV4/LJAedeMy5joUBYQWvSJj6FYZ3 SVo+UzanfLzomzf4niVBYbOt7tSp315z3o/2+cd76eTf02r1ex2Xs1sYjuwpuorHCv a/7YdCTfY+qSA== Date: Tue, 15 Mar 2022 11:46:45 +0000 From: Filipe Manana To: Johannes Thumshirn Cc: David Sterba , Josef Bacik , linux-btrfs@vger.kernel.org Subject: Re: [PATCH v3] btrfs: zoned: make auto-reclaim less aggressive Message-ID: References: <74cbd8cdefe76136b3f9fb9b96bddfcbcd5b5861.1647342146.git.johannes.thumshirn@wdc.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <74cbd8cdefe76136b3f9fb9b96bddfcbcd5b5861.1647342146.git.johannes.thumshirn@wdc.com> Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org On Tue, Mar 15, 2022 at 04:02:57AM -0700, Johannes Thumshirn wrote: > The current auto-reclaim algorithm starts reclaiming all block-group's > with a zone_unusable value above a configured threshold. This is causing a > lot of reclaim IO even if there would be enough free zones on the device. > > Instead of only accounting a block-group's zone_unusable value, also take > the number of empty zones into account. > > Cc: Josef Bacik > Signed-off-by: Johannes Thumshirn > > --- > Changes since v4: > * Use div_u64() > > Changes since RFC: > * Fix logic error > * Skip unavailable devices > * Use different metric working for non-zoned devices as well > --- > fs/btrfs/block-group.c | 3 +++ > fs/btrfs/zoned.c | 30 ++++++++++++++++++++++++++++++ > fs/btrfs/zoned.h | 6 ++++++ > 3 files changed, 39 insertions(+) > > diff --git a/fs/btrfs/block-group.c b/fs/btrfs/block-group.c > index c22d287e020b..2e77b38c538b 100644 > --- a/fs/btrfs/block-group.c > +++ b/fs/btrfs/block-group.c > @@ -1522,6 +1522,9 @@ void btrfs_reclaim_bgs_work(struct work_struct *work) > if (!test_bit(BTRFS_FS_OPEN, &fs_info->flags)) > return; > > + if (!btrfs_zoned_should_reclaim(fs_info)) > + return; > + > sb_start_write(fs_info->sb); > > if (!btrfs_exclop_start(fs_info, BTRFS_EXCLOP_BALANCE)) { > diff --git a/fs/btrfs/zoned.c b/fs/btrfs/zoned.c > index 49446bb5a5d1..dc62a14594de 100644 > --- a/fs/btrfs/zoned.c > +++ b/fs/btrfs/zoned.c > @@ -15,6 +15,7 @@ > #include "transaction.h" > #include "dev-replace.h" > #include "space-info.h" > +#include "misc.h" Why is this included added? Did you intended to use div_factor()? Thanks. > > /* Maximum number of zones to report per blkdev_report_zones() call */ > #define BTRFS_REPORT_NR_ZONES 4096 > @@ -2078,3 +2079,32 @@ void btrfs_free_zone_cache(struct btrfs_fs_info *fs_info) > } > mutex_unlock(&fs_devices->device_list_mutex); > } > + > +bool btrfs_zoned_should_reclaim(struct btrfs_fs_info *fs_info) > +{ > + struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; > + struct btrfs_device *device; > + u64 bytes_used = 0; > + u64 total_bytes = 0; > + u64 factor; > + > + if (!btrfs_is_zoned(fs_info)) > + return false; > + > + if (!fs_info->bg_reclaim_threshold) > + return false; > + > + mutex_lock(&fs_devices->device_list_mutex); > + list_for_each_entry(device, &fs_devices->devices, dev_list) { > + if (!device->bdev) > + continue; > + > + total_bytes += device->disk_total_bytes; > + bytes_used += device->bytes_used; > + > + } > + mutex_unlock(&fs_devices->device_list_mutex); > + > + factor = div_u64(bytes_used * 100, total_bytes); > + return factor >= fs_info->bg_reclaim_threshold; > +} > diff --git a/fs/btrfs/zoned.h b/fs/btrfs/zoned.h > index cbf016a7bb5d..d0d0e5c02606 100644 > --- a/fs/btrfs/zoned.h > +++ b/fs/btrfs/zoned.h > @@ -78,6 +78,7 @@ void btrfs_zone_finish_endio(struct btrfs_fs_info *fs_info, u64 logical, > u64 length); > void btrfs_clear_data_reloc_bg(struct btrfs_block_group *bg); > void btrfs_free_zone_cache(struct btrfs_fs_info *fs_info); > +bool btrfs_zoned_should_reclaim(struct btrfs_fs_info *fs_info); > #else /* CONFIG_BLK_DEV_ZONED */ > static inline int btrfs_get_dev_zone(struct btrfs_device *device, u64 pos, > struct blk_zone *zone) > @@ -236,6 +237,11 @@ static inline void btrfs_zone_finish_endio(struct btrfs_fs_info *fs_info, > static inline void btrfs_clear_data_reloc_bg(struct btrfs_block_group *bg) { } > > static inline void btrfs_free_zone_cache(struct btrfs_fs_info *fs_info) { } > + > +static inline bool btrfs_zoned_should_reclaim(struct btrfs_fs_info *fs_info) > +{ > + return false; > +} > #endif > > static inline bool btrfs_dev_is_sequential(struct btrfs_device *device, u64 pos) > -- > 2.35.1 >