Btrfs: don't wait as long for more batches during SSD log commit (cd354ad6) · Commits · 戴 / test

When we're doing log commits, we try to wait for more writers to come in and make the commit bigger. This helps improve performance on rotating disks, but on SSDs it adds latencies. Signed-off-by:

Chris Mason <chris.mason@oracle.com>

fs/btrfs/tree-log.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -2013,10 +2013,10 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans,
		/* wait for previous tree log sync to complete */
		if (atomic_read(&root->log_commit[(index1 + 1) % 2]))
		wait_log_commit(trans, root, root->log_transid - 1);

		while (1) {
		unsigned long batch = root->log_batch;
		if (root->log_multiple_pids) {
		/* when we're on an ssd, just kick the log commit out */
		if (!btrfs_test_opt(root, SSD) && root->log_multiple_pids) {
		mutex_unlock(&root->log_mutex);
		schedule_timeout_uninterruptible(1);
		mutex_lock(&root->log_mutex);

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