diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index f82f8db02275912ec50dba3e18a31e698bed183a..ac61c50a331156d73d864a78067636b45817d500 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -1285,16 +1285,16 @@ static noinline void reada_for_search(struct btrfs_root *root,
 		}
 		search = btrfs_node_blockptr(node, nr);
 		if ((search >= lowest_read && search <= highest_read) ||
-		    (search < lowest_read && lowest_read - search <= 32768) ||
-		    (search > highest_read && search - highest_read <= 32768)) {
+		    (search < lowest_read && lowest_read - search <= 16384) ||
+		    (search > highest_read && search - highest_read <= 16384)) {
 			readahead_tree_block(root, search, blocksize,
 				     btrfs_node_ptr_generation(node, nr));
 			nread += blocksize;
 		}
 		nscan++;
-		if (path->reada < 2 && (nread > (256 * 1024) || nscan > 32))
+		if (path->reada < 2 && (nread > (64 * 1024) || nscan > 32))
 			break;
-		if(nread > (1024 * 1024) || nscan > 128)
+		if(nread > (256 * 1024) || nscan > 128)
 			break;
 
 		if (search < lowest_read)
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 1bb54d69fbb24416f80a2fd17151274c64042577..3b0e974a9e9c5aec034139852f7cc458ac67a0db 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -605,7 +605,7 @@ static int btree_submit_bio_hook(struct inode *inode, int rw, struct bio *bio,
 		BUG_ON(ret);
 
 		return btrfs_map_bio(BTRFS_I(inode)->root, rw, bio,
-				     mirror_num, 1);
+				     mirror_num, 0);
 	}
 	return btrfs_wq_submit_bio(BTRFS_I(inode)->root->fs_info,
 				   inode, rw, bio, mirror_num, 0,
@@ -1139,11 +1139,11 @@ static int btrfs_congested_fn(void *congested_data, int bdi_bits)
 	struct list_head *cur;
 	struct btrfs_device *device;
 	struct backing_dev_info *bdi;
-
+#if 0
 	if ((bdi_bits & (1 << BDI_write_congested)) &&
 	    btrfs_congested_async(info, 0))
 		return 1;
-
+#endif
 	list_for_each(cur, &info->fs_devices->devices) {
 		device = list_entry(cur, struct btrfs_device, dev_list);
 		if (!device->bdev)