summaryrefslogtreecommitdiff
path: root/fs/jbd2/transaction.c
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2009-01-08 17:14:59 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2009-01-08 17:14:59 -0800
commit2150edc6c5cf00f7adb54538b9ea2a3e9cedca3f (patch)
treef72a0d85e66f500b4cead348a231e3d3b9f357bc /fs/jbd2/transaction.c
parentcd764695b67386a81964f68e9c66efd9f13f4d29 (diff)
parent4b905671d2ea09fd48fed72c581df17e40823f39 (diff)
Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (57 commits) jbd2: Fix oops in jbd2_journal_init_inode() on corrupted fs ext4: Remove "extents" mount option block: Add Kconfig help which notes that ext4 needs CONFIG_LBD ext4: Make printk's consistently prefixed with "EXT4-fs: " ext4: Add sanity checks for the superblock before mounting the filesystem ext4: Add mount option to set kjournald's I/O priority jbd2: Submit writes to the journal using WRITE_SYNC jbd2: Add pid and journal device name to the "kjournald2 starting" message ext4: Add markers for better debuggability ext4: Remove code to create the journal inode ext4: provide function to release metadata pages under memory pressure ext3: provide function to release metadata pages under memory pressure add releasepage hooks to block devices which can be used by file systems ext4: Fix s_dirty_blocks_counter if block allocation failed with nodelalloc ext4: Init the complete page while building buddy cache ext4: Don't allow new groups to be added during block allocation ext4: mark the blocks/inode bitmap beyond end of group as used ext4: Use new buffer_head flag to check uninit group bitmaps initialization ext4: Fix the race between read_inode_bitmap() and ext4_new_inode() ext4: code cleanup ...
Diffstat (limited to 'fs/jbd2/transaction.c')
-rw-r--r--fs/jbd2/transaction.c60
1 files changed, 46 insertions, 14 deletions
diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c
index 4f925a4f3d05..46b4e347ed7d 100644
--- a/fs/jbd2/transaction.c
+++ b/fs/jbd2/transaction.c
@@ -25,6 +25,7 @@
#include <linux/timer.h>
#include <linux/mm.h>
#include <linux/highmem.h>
+#include <linux/hrtimer.h>
static void __jbd2_journal_temp_unlink_buffer(struct journal_head *jh);
@@ -48,6 +49,7 @@ jbd2_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);
@@ -1240,7 +1242,7 @@ int jbd2_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);
@@ -1263,24 +1265,54 @@ int jbd2_journal_stop(handle_t *handle)
/*
* Implement synchronous transaction batching. If the handle
* was synchronous, don't force a commit immediately. Let's
- * yield and let another thread piggyback onto this transaction.
- * Keep doing that while new threads continue to arrive.
- * It doesn't cost much - we're about to run a commit and sleep
- * on IO anyway. Speeds up many-threaded, many-dir operations
- * by 30x or more...
+ * yield and let another thread piggyback onto this
+ * transaction. Keep doing that while new threads continue to
+ * arrive. It doesn't cost much - we're about to run a commit
+ * and sleep 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 useful 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 achieve 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
- * for joiners in that case.
+ * 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 for joiners in that case.
*/
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 = max_t(u64, commit_time,
+ 1000*journal->j_min_batch_time);
+ commit_time = min_t(u64, commit_time,
+ 1000*journal->j_max_batch_time);
+
+ 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;