linux-kernel - [PATCH 1/2] f2fs: use IPU for cold files

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Date:   Mon,  7 Aug 2017 18:42:21 -0700
From:   Jaegeuk Kim <jaegeuk@...nel.org>
To:     linux-kernel@...r.kernel.org, linux-fsdevel@...r.kernel.org,
        linux-f2fs-devel@...ts.sourceforge.net
Cc:     Jaegeuk Kim <jaegeuk@...nel.org>
Subject: [PATCH 1/2] f2fs: use IPU for cold files

We expect cold files write data sequentially, but sometimes some of small data
can be updated, which incurs fragmentation.
Let's avoid that.

Signed-off-by: Jaegeuk Kim <jaegeuk@...nel.org>
---
 fs/f2fs/segment.h | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/fs/f2fs/segment.h b/fs/f2fs/segment.h
index 6b871b492fd5..7f700e54b77d 100644
--- a/fs/f2fs/segment.h
+++ b/fs/f2fs/segment.h
@@ -577,6 +577,10 @@ static inline bool need_inplace_update_policy(struct inode *inode,
 	if (test_opt(sbi, LFS))
 		return false;
 
+	/* if this is cold file, we should overwrite to avoid fragmentation */
+	if (file_is_cold(inode))
+		return true;
+
 	if (policy & (0x1 << F2FS_IPU_FORCE))
 		return true;
 	if (policy & (0x1 << F2FS_IPU_SSR) && need_SSR(sbi))
-- 
2.13.0.rc1.294.g07d810a77f-goog