diff --git a/sys/boot/forth/loader.4th b/sys/boot/forth/loader.4th
index f002c0774e82..f4d7666d2c24 100644
--- a/sys/boot/forth/loader.4th
+++ b/sys/boot/forth/loader.4th
@@ -48,6 +48,9 @@ s" arch-i386" environment? [if] [if]
 	[then]
 [then] [then]
 
+256 dictthreshold !  \ 256 cells minimum free space
+2048 dictincrease !  \ 2048 additional cells each time
+
 include /boot/support.4th
 
 \ ***** boot-conf