diff --git a/common_power.h b/common_power.h
index a61e4e28a..6fb2af30a 100644
--- a/common_power.h
+++ b/common_power.h
@@ -849,6 +849,10 @@ Lmcount$lazy_ptr:
 #else
 #define BUFFER_SIZE     ( 16 << 20)
 #endif
+#ifeq ($(DYNAMIC_ARCH), 1)
+#undefine BUFFER_SIZE
+#define BUFFER_SIZE (64 << 22)
+#endif
 
 #ifndef PAGESIZE
 #define PAGESIZE	( 4 << 10)