linux-kernel - [PATCH] f2fs: set default valid_thresh

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Message-ID: <20251003224917.1950708-1-daeho43@gmail.com>
Date: Fri,  3 Oct 2025 15:49:17 -0700
From: Daeho Jeong <daeho43@...il.com>
To: linux-kernel@...r.kernel.org,
	linux-f2fs-devel@...ts.sourceforge.net,
	kernel-team@...roid.com
Cc: Daeho Jeong <daehojeong@...gle.com>
Subject: [PATCH] f2fs: set default valid_thresh_ratio to 80 for zoned devices

From: Daeho Jeong <daehojeong@...gle.com>

Zoned storage devices provide marginal over-capacity space, typically
around 10%, for filesystem level storage control.

By utilizing this extra capacity, we can safely reduce the default
'valid_thresh_ratio' to 80. This action helps to significantly prevent
excessive garbage collection (GC) and the resulting power consumption,
as the filesystem becomes less aggressive about cleaning segments
that still hold a high percentage of valid data.

Signed-off-by: Daeho Jeong <daehojeong@...gle.com>
---
 fs/f2fs/gc.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/f2fs/gc.h b/fs/f2fs/gc.h
index 24e8b1c27acc..6c4d4567571e 100644
--- a/fs/f2fs/gc.h
+++ b/fs/f2fs/gc.h
@@ -25,7 +25,7 @@
 #define DEF_GC_THREAD_CANDIDATE_RATIO		20	/* select 20% oldest sections as candidates */
 #define DEF_GC_THREAD_MAX_CANDIDATE_COUNT	10	/* select at most 10 sections as candidates */
 #define DEF_GC_THREAD_AGE_WEIGHT		60	/* age weight */
-#define DEF_GC_THREAD_VALID_THRESH_RATIO	95	/* do not GC over 95% valid block ratio for one time GC */
+#define DEF_GC_THREAD_VALID_THRESH_RATIO	80	/* do not GC over 80% valid block ratio for one time GC */
 #define DEFAULT_ACCURACY_CLASS			10000	/* accuracy class */
 
 #define LIMIT_INVALID_BLOCK	40 /* percentage over total user space */
-- 
2.51.0.618.g983fd99d29-goog