From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 701BC19AD48 for ; Tue, 16 Sep 2025 02:28:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757989685; cv=none; b=ILMpfFloxQzv81CF+F8ZTHmefeitjEnneyx7UTSZL+dqW1neuEd/7Y5eMnug2zwEAbXzdL0CnDGLNZQgp5ffKt4naMVPIGilrBMvgnkyeVy3214IwuW+YyAl5CDdQmVr6FidnvBR3iyq2dNwUZiINndxNP62TNtyS8148nH0zw4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757989685; c=relaxed/simple; bh=cUI+GduIRyVlpYvUYsfmG89UKOgODbBvtSJCHqDtaKc=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=QA8xMXG9ysrFO6ls1BTuBA1lF5XB3IstyPCJLEymlu7TvIOouL3YtI8YEuScRmvYwFYWrRPhxDnDgor+rV3yPHo2yizqEhZ4bSKCPpR1abJUMLU6KbcofuN3ODMEXk9kdo/D0dFXt6QmabzPG1fZ70aDh0xUHsrs5fGdykKDCi8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=nrTQFkQi; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="nrTQFkQi" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 08B9FC4CEF1; Tue, 16 Sep 2025 02:28:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1757989685; bh=cUI+GduIRyVlpYvUYsfmG89UKOgODbBvtSJCHqDtaKc=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=nrTQFkQi9jBkK0BqRbPVRHBZyi3fKTIRjMbAYnNeJ+jizcWiR1PgMBGuk+vmHHIva U/IvUOU1oyqP8Y27t1o/5hCdrrRTI7qT3NYNNdTqZQ/kHLZE0vTviudJjGQaIyyD+6 7p8sjoCaraZFYZisWtA7JFex45QzP+6L2bDIYj5Jathst6GRD0CUrnHaaNknJbTspw 2HnLKNeVYpLRoSRwpiRTPokrT7vHMz9wTfCfcjoPWsnCAQK2z3xdwCEVAexRoKFXKw Xep0vcqGSAw6fFJRAWmoGVowzcPUZUM6vxRh1j9aPJW1AgD8l9dHk1VbynFQyNuU7H qFMlfdAgy+04Q== Date: Tue, 16 Sep 2025 02:28:03 +0000 From: Jaegeuk Kim To: Liao Yuanhong Cc: Chao Yu , "open list:F2FS FILE SYSTEM" , open list Subject: Re: [PATCH 1/2] f2fs: Optimize excessive write operations caused by continuous background garbage collection in Zoned UFS Message-ID: References: <20250909134418.502922-1-liaoyuanhong@vivo.com> <20250909134418.502922-2-liaoyuanhong@vivo.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250909134418.502922-2-liaoyuanhong@vivo.com> Could you please share some trends of relation between has_enough_free_blocks() vs. has_enough_dirty_blocks()? I'm wondering whethere there's a missing case where has_enough_free_blocks() is not enough. On 09/09, Liao Yuanhong wrote: > Incorporate a check using has_enough_dirty_blocks() to prevent redundant > background GC in Zoned UFS. When there are insufficient dirty segments, > continuous execution of background GC should be avoided, as it results in > unnecessary write operations and impacts device lifespan. The initial > threshold is set to 3 * section size (since f2fs data uses three write > pointers). > > Signed-off-by: Liao Yuanhong > --- > fs/f2fs/gc.c | 8 ++++++-- > fs/f2fs/gc.h | 10 +++++++++- > 2 files changed, 15 insertions(+), 3 deletions(-) > > diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c > index ed3acbfc83ca..4a8c08f970e3 100644 > --- a/fs/f2fs/gc.c > +++ b/fs/f2fs/gc.c > @@ -120,7 +120,9 @@ static int gc_thread_func(void *data) > > if (f2fs_sb_has_blkzoned(sbi)) { > if (has_enough_free_blocks(sbi, > - gc_th->no_zoned_gc_percent)) { > + gc_th->no_zoned_gc_percent) || > + !has_enough_dirty_blocks(sbi, > + LIMIT_GC_DIRTY_SECTION_NUM)) { > wait_ms = gc_th->no_gc_sleep_time; > f2fs_up_write(&sbi->gc_lock); > goto next; > @@ -1750,7 +1752,9 @@ static int do_garbage_collect(struct f2fs_sb_info *sbi, > > if (f2fs_sb_has_blkzoned(sbi) && > !has_enough_free_blocks(sbi, > - sbi->gc_thread->boost_zoned_gc_percent)) > + sbi->gc_thread->boost_zoned_gc_percent) && > + has_enough_dirty_blocks(sbi, > + LIMIT_GC_DIRTY_SECTION_NUM)) > window_granularity *= > sbi->gc_thread->boost_gc_multiple; > > diff --git a/fs/f2fs/gc.h b/fs/f2fs/gc.h > index 24e8b1c27acc..1ef234c2702b 100644 > --- a/fs/f2fs/gc.h > +++ b/fs/f2fs/gc.h > @@ -36,6 +36,7 @@ > #define DEF_MIGRATION_WINDOW_GRANULARITY_ZONED 3 > #define BOOST_GC_MULTIPLE 5 > #define ZONED_PIN_SEC_REQUIRED_COUNT 1 > +#define LIMIT_GC_DIRTY_SECTION_NUM 3 > > #define DEF_GC_FAILED_PINNED_FILES 2048 > #define MAX_GC_FAILED_PINNED_FILES USHRT_MAX > @@ -177,6 +178,12 @@ static inline bool has_enough_free_blocks(struct f2fs_sb_info *sbi, > return free_sections(sbi) > ((sbi->total_sections * limit_perc) / 100); > } > > +static inline bool has_enough_dirty_blocks(struct f2fs_sb_info *sbi, > + unsigned int limit_num) > +{ > + return dirty_segments(sbi) > limit_num * SEGS_PER_SEC(sbi); > +} > + > static inline bool has_enough_invalid_blocks(struct f2fs_sb_info *sbi) > { > block_t user_block_count = sbi->user_block_count; > @@ -197,6 +204,7 @@ static inline bool need_to_boost_gc(struct f2fs_sb_info *sbi) > { > if (f2fs_sb_has_blkzoned(sbi)) > return !has_enough_free_blocks(sbi, > - sbi->gc_thread->boost_zoned_gc_percent); > + sbi->gc_thread->boost_zoned_gc_percent) && > + has_enough_dirty_blocks(sbi, LIMIT_GC_DIRTY_SECTION_NUM); > return has_enough_invalid_blocks(sbi); > } > -- > 2.34.1