diff --git a/lib/guestfs-internal.h b/lib/guestfs-internal.h
index 75b8a5c8e..30553d7c0 100644
--- a/lib/guestfs-internal.h
+++ b/lib/guestfs-internal.h
@@ -94,7 +94,7 @@
  * creating device nodes.
  */
 #ifdef __powerpc__
-#  define DEFAULT_MEMSIZE 1024
+#  define DEFAULT_MEMSIZE 1280
 #endif
 
 /* Kernel 3.19 is unable to uncompress the initramfs on aarch64 unless
@@ -103,12 +103,12 @@
  * common on aarch64, treat this like the ppc case above.
  */
 #ifdef __aarch64__
-#  define DEFAULT_MEMSIZE 1024
+#  define DEFAULT_MEMSIZE 1280
 #endif
 
 /* The default and minimum memory size for most users. */
 #ifndef DEFAULT_MEMSIZE
-#  define DEFAULT_MEMSIZE 768
+#  define DEFAULT_MEMSIZE 1280
 #endif
 #ifndef MIN_MEMSIZE
 #  define MIN_MEMSIZE 256