diff --git a/arch/x86/xen/Kconfig b/arch/x86/xen/Kconfig
index 26c731a..fdce49c 100644
--- a/arch/x86/xen/Kconfig
+++ b/arch/x86/xen/Kconfig
@@ -29,7 +29,8 @@
 
 config XEN_MAX_DOMAIN_MEMORY
        int
-       default 128
+       default 500 if X86_64
+       default 64 if X86_32
        depends on XEN
        help
          This only affects the sizing of some bss arrays, the unused
@@ -48,3 +49,4 @@
 	help
 	  Enable statistics output and various tuning options in debugfs.
 	  Enabling this option may incur a significant performance overhead.
+