btrfs: add mount option to set commit interval
I'ts hardcoded to 30 seconds which is fine for most users. Higher values
defer data being synced to permanent storage with obvious consequences
when the system crashes. The upper bound is not forced, but a warning is
printed if it's more than 300 seconds (5 minutes).
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 2a378ab..572e21e 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -1742,7 +1742,7 @@
do {
cannot_commit = false;
- delay = HZ * 30;
+ delay = HZ * root->fs_info->commit_interval;
mutex_lock(&root->fs_info->transaction_kthread_mutex);
spin_lock(&root->fs_info->trans_lock);
@@ -1754,7 +1754,8 @@
now = get_seconds();
if (cur->state < TRANS_STATE_BLOCKED &&
- (now < cur->start_time || now - cur->start_time < 30)) {
+ (now < cur->start_time ||
+ now - cur->start_time < root->fs_info->commit_interval)) {
spin_unlock(&root->fs_info->trans_lock);
delay = HZ * 5;
goto sleep;
@@ -2194,6 +2195,7 @@
fs_info->defrag_inodes = RB_ROOT;
fs_info->free_chunk_space = 0;
fs_info->tree_mod_log = RB_ROOT;
+ fs_info->commit_interval = BTRFS_DEFAULT_COMMIT_INTERVAL;
/* readahead state */
INIT_RADIX_TREE(&fs_info->reada_tree, GFP_NOFS & ~__GFP_WAIT);