| Message ID | 1359524369-31234-1-git-send-email-tytso@mit.edu |
|---|---|
| State | Superseded, archived |
| Headers | show |
diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c index dbf41f9..1a80e31 100644 --- a/fs/jbd2/journal.c +++ b/fs/jbd2/journal.c @@ -513,6 +513,10 @@ int __jbd2_log_space_left(journal_t *journal) */ int __jbd2_log_start_commit(journal_t *journal, tid_t target) { + /* Return if the txn has already requested to be committed */ + if (journal->j_commit_request == target) + return 0; + /* * The only transaction we can possibly wait upon is the * currently running transaction (if it exists). Otherwise,
Don't send an extra wakeup to kjournald in the case where we already have the proper target in j_commit_request, i.e. that transaction has already been requested for commit. commit deeeaf13 "jbd2: fix fsync() tid wraparound bug" changed the logic leading to a wakeup, but it caused some extra wakeups which were found to lead to a measurable performance regression. Reported-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: Eric Sandeen <sandeen@redhat.com> Cc: Sedat Dilek <sedat.dilek@gmail.com> Cc: mszeredi@suse.cz --- Eric, I think this might be clearer than the patch which you proposed; what do you think? fs/jbd2/journal.c | 4 ++++ 1 file changed, 4 insertions(+)