diff options
Diffstat (limited to 'fs/jbd/transaction.c')
-rw-r--r-- | fs/jbd/transaction.c | 39 |
1 files changed, 33 insertions, 6 deletions
diff --git a/fs/jbd/transaction.c b/fs/jbd/transaction.c index 60d4c32c880..e6a11743127 100644 --- a/fs/jbd/transaction.c +++ b/fs/jbd/transaction.c @@ -25,6 +25,7 @@ #include <linux/timer.h> #include <linux/mm.h> #include <linux/highmem.h> +#include <linux/hrtimer.h> static void __journal_temp_unlink_buffer(struct journal_head *jh); @@ -49,6 +50,7 @@ get_transaction(journal_t *journal, transaction_t *transaction) { transaction->t_journal = journal; transaction->t_state = T_RUNNING; + transaction->t_start_time = ktime_get(); transaction->t_tid = journal->j_transaction_sequence++; transaction->t_expires = jiffies + journal->j_commit_interval; spin_lock_init(&transaction->t_handle_lock); @@ -752,7 +754,6 @@ out: * int journal_get_write_access() - notify intent to modify a buffer for metadata (not data) update. * @handle: transaction to add buffer modifications to * @bh: bh to be used for metadata writes - * @credits: variable that will receive credits for the buffer * * Returns an error code or 0 on success. * @@ -1370,7 +1371,7 @@ int journal_stop(handle_t *handle) { transaction_t *transaction = handle->h_transaction; journal_t *journal = transaction->t_journal; - int old_handle_count, err; + int err; pid_t pid; J_ASSERT(journal_current_handle() == handle); @@ -1399,6 +1400,17 @@ int journal_stop(handle_t *handle) * on IO anyway. Speeds up many-threaded, many-dir operations * by 30x or more... * + * We try and optimize the sleep time against what the underlying disk + * can do, instead of having a static sleep time. This is usefull for + * the case where our storage is so fast that it is more optimal to go + * ahead and force a flush and wait for the transaction to be committed + * than it is to wait for an arbitrary amount of time for new writers to + * join the transaction. We acheive this by measuring how long it takes + * to commit a transaction, and compare it with how long this + * transaction has been running, and if run time < commit time then we + * sleep for the delta and commit. This greatly helps super fast disks + * that would see slowdowns as more threads started doing fsyncs. + * * But don't do this if this process was the most recent one to * perform a synchronous write. We do this to detect the case where a * single process is doing a stream of sync writes. No point in waiting @@ -1406,11 +1418,26 @@ int journal_stop(handle_t *handle) */ pid = current->pid; if (handle->h_sync && journal->j_last_sync_writer != pid) { + u64 commit_time, trans_time; + journal->j_last_sync_writer = pid; - do { - old_handle_count = transaction->t_handle_count; - schedule_timeout_uninterruptible(1); - } while (old_handle_count != transaction->t_handle_count); + + spin_lock(&journal->j_state_lock); + commit_time = journal->j_average_commit_time; + spin_unlock(&journal->j_state_lock); + + trans_time = ktime_to_ns(ktime_sub(ktime_get(), + transaction->t_start_time)); + + commit_time = min_t(u64, commit_time, + 1000*jiffies_to_usecs(1)); + + if (trans_time < commit_time) { + ktime_t expires = ktime_add_ns(ktime_get(), + commit_time); + set_current_state(TASK_UNINTERRUPTIBLE); + schedule_hrtimeout(&expires, HRTIMER_MODE_ABS); + } } current->journal_info = NULL; |