diff options
| author | Julian Sun <sunjunchao@bytedance.com> | 2025-08-27 20:18:12 +0800 |
|---|---|---|
| committer | Theodore Ts'o <tytso@mit.edu> | 2025-09-25 14:56:31 -0400 |
| commit | 46e75c56dfeafb6756773b71cabe187a6886859a (patch) | |
| tree | 66dbc42c5a29602865c8f5568aa4c93805b5106b /fs/ext4/fast_commit.c | |
| parent | ext4: remove obsolete EXT3 config options (diff) | |
| download | linux-46e75c56dfeafb6756773b71cabe187a6886859a.tar.gz linux-46e75c56dfeafb6756773b71cabe187a6886859a.zip | |
ext4: increase IO priority of fastcommit
The following code paths may result in high latency or even task hangs:
1. fastcommit io is throttled by wbt.
2. jbd2_fc_wait_bufs() might wait for a long time while
JBD2_FAST_COMMIT_ONGOING is set in journal->flags, and then
jbd2_journal_commit_transaction() waits for the
JBD2_FAST_COMMIT_ONGOING bit for a long time while holding the write
lock of j_state_lock.
3. start_this_handle() waits for read lock of j_state_lock which
results in high latency or task hang.
Given the fact that ext4_fc_commit() already modifies the current
process' IO priority to match that of the jbd2 thread, it should be
reasonable to match jbd2's IO submission flags as well.
Suggested-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Signed-off-by: Julian Sun <sunjunchao@bytedance.com>
Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-ID: <20250827121812.1477634-1-sunjunchao@bytedance.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Diffstat (limited to 'fs/ext4/fast_commit.c')
| -rw-r--r-- | fs/ext4/fast_commit.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/fs/ext4/fast_commit.c b/fs/ext4/fast_commit.c index 42bee1d4f9f9..fa66b08de999 100644 --- a/fs/ext4/fast_commit.c +++ b/fs/ext4/fast_commit.c @@ -663,7 +663,7 @@ void ext4_fc_track_range(handle_t *handle, struct inode *inode, ext4_lblk_t star static void ext4_fc_submit_bh(struct super_block *sb, bool is_tail) { - blk_opf_t write_flags = REQ_SYNC; + blk_opf_t write_flags = JBD2_JOURNAL_REQ_FLAGS; struct buffer_head *bh = EXT4_SB(sb)->s_fc_bh; /* Add REQ_FUA | REQ_PREFLUSH only its tail */ |