diff --git a/test/unit/binshard.sh b/test/unit/binshard.sh
index c1d58c88..1882e90a 100644
--- a/test/unit/binshard.sh
+++ b/test/unit/binshard.sh
@@ -1,3 +1,3 @@
 #!/bin/sh
 
-export MALLOC_CONF="narenas:1,bin_shards:1-160:16|129-512:4|256-256:8"
+export MALLOC_CONF="narenas:1,bin_shards:1-160:16|129-512:4|256-256:8|513-8070450532247928832:1"