diff --git a/page.go b/page.go
index b3dc473..de2e623 100644
--- a/page.go
+++ b/page.go
@@ -8,7 +8,7 @@ import (
 
 const pageHeaderSize = int(unsafe.Offsetof(((*page)(nil)).ptr))
 
-const maxAllocSize = 0xFFFFFFF
+const maxAllocSize = 0x7FFFFFFF
 const minKeysPerPage = 2
 
 const branchPageElementSize = int(unsafe.Sizeof(branchPageElement{}))