Btrfs: add mount -o auto_defrag
This will detect small random writes into files and
queue the up for an auto defrag process. It isn't well suited to
database workloads yet, but works for smaller files such as rpm, sqlite
or bdb databases.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index cd0c7cd..28e3cb2 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -160,7 +160,7 @@
Opt_compress_type, Opt_compress_force, Opt_compress_force_type,
Opt_notreelog, Opt_ratio, Opt_flushoncommit, Opt_discard,
Opt_space_cache, Opt_clear_cache, Opt_user_subvol_rm_allowed,
- Opt_enospc_debug, Opt_subvolrootid, Opt_err,
+ Opt_enospc_debug, Opt_subvolrootid, Opt_defrag, Opt_err,
};
static match_table_t tokens = {
@@ -191,6 +191,7 @@
{Opt_user_subvol_rm_allowed, "user_subvol_rm_allowed"},
{Opt_enospc_debug, "enospc_debug"},
{Opt_subvolrootid, "subvolrootid=%d"},
+ {Opt_defrag, "autodefrag"},
{Opt_err, NULL},
};
@@ -369,6 +370,10 @@
case Opt_enospc_debug:
btrfs_set_opt(info->mount_opt, ENOSPC_DEBUG);
break;
+ case Opt_defrag:
+ printk(KERN_INFO "btrfs: enabling auto defrag");
+ btrfs_set_opt(info->mount_opt, AUTO_DEFRAG);
+ break;
case Opt_err:
printk(KERN_INFO "btrfs: unrecognized mount option "
"'%s'\n", p);