diff --git a/lib/mempool.c b/lib/mempool.c
index 65072f9a..ec9854a9 100644
--- a/lib/mempool.c
+++ b/lib/mempool.c
@@ -250,7 +250,7 @@ lp_memsize(resource *r)
     cnt++;
 
   return ALLOC_OVERHEAD + sizeof(struct linpool) +
-    cnt * (ALLOC_OVERHEAD + sizeof(sizeof(struct lp_chunk))) +
+    cnt * (ALLOC_OVERHEAD + sizeof(struct lp_chunk)) +
     m->total + m->total_large;
 }