On 10/16/2025 1:16 PM, Jeuk Kim wrote:
From: Jeuk Kim <[email protected]>Inline encryption derives DUN from <inode, file offset>, so bios from different inodes can't merge. With multi-threaded buffered O_SYNC writes where each thread writes to its own file, 4KiB-per-page LBA allocation interleaves across inodes and causes bio split. Serialize writeback for fscrypt inline-crypto inodes via __should_serialize_io() to keep foreground writeback focused on one inode and avoid split. Test: fio --name=wb_osync --rw=write --bs=1M \ --time_based=1 --runtime=60s --size=2G \ --ioengine=psync --direct=0 --sync=1 \ --numjobs=8 --thread=1 --nrfiles=1 \ --filename_format='wb_osync.$jobnum' device: UFS Before - write throughput: 675MiB/s device I/O size distribution (by count, total 1027414): 4 KiB: 923139 (89.9%) 8 KiB: 84798 (8.3%) ≥512 KiB: 453 (0.0%) After - write throughput: 1760MiB/s device I/O size distribution (by count, total 231750): 4 KiB: 16904 (7.3%) 8 KiB: 72128 (31.1%) ≥512 KiB: 118900 (51.3%) Signed-off-by: Jeuk Kim <[email protected]> --- fs/f2fs/data.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c index ef38e62cda8f..ae6fb435d576 100644 --- a/fs/f2fs/data.c +++ b/fs/f2fs/data.c @@ -3217,6 +3217,8 @@ static inline bool __should_serialize_io(struct inode *inode,if (f2fs_need_compress_data(inode))return true; + if (fscrypt_inode_uses_inline_crypto(inode)) + return true; if (wbc->sync_mode != WB_SYNC_ALL) return true; if (get_dirty_pages(inode) >= SM_I(F2FS_I_SB(inode))->min_seq_blocks)
Jeuk, Can you please try tuning /sys/fs/f2fs/<dev>/min_seq_blocks to see whether it can achive the goal? Thanks, _______________________________________________ Linux-f2fs-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel
