diff --git a/build_library/disk_layout.json b/build_library/disk_layout.json
index d10d60a638..ff16124d49 100644
--- a/build_library/disk_layout.json
+++ b/build_library/disk_layout.json
@@ -62,7 +62,7 @@
       "9":{
         "label":"ROOT",
         "type":"coreos-resize",
-        "blocks":"1048576",
+        "blocks":"4194304",
         "fs_type":"btrfs",
         "fs_subvolume":"root",
         "mount":"/"
@@ -71,7 +71,7 @@
     "vm":{
       "9":{
         "label":"ROOT",
-        "blocks":"6291456"
+        "blocks":"12582912"
       }
     },
     "vagrant":{
diff --git a/build_library/disk_util b/build_library/disk_util
index 3c6001984c..3f0c23b6ac 100755
--- a/build_library/disk_util
+++ b/build_library/disk_util
@@ -342,11 +342,6 @@ def FormatBtrfs(part, device):
   """
   Sudo(['mkfs.btrfs', '--byte-count', part['fs_bytes'],
                       '--label', part['label'],
-                      # must use mixed chunks at this point because
-                      # the filesystem size is too small.
-                      '--data', 'single',
-                      '--metadata', 'single',
-                      '--mixed',
                       device])
 
   if part.get('fs_subvolume', None):