diff --git a/node-ram-cache.c b/node-ram-cache.c
index 496fc1779..d2377601d 100644
--- a/node-ram-cache.c
+++ b/node-ram-cache.c
@@ -356,7 +356,7 @@ void init_node_ram_cache( int strategy, int cacheSizeMB, int fixpointscale ) {
     cacheSize = (int64_t)cacheSizeMB*(1024*1024);
     /* How much we can fit, and make sure it's odd */
     maxBlocks = (cacheSize/(PER_BLOCK*sizeof(struct ramNode)));
-    maxSparseTuples = (cacheSize/sizeof(struct ramNodeID));
+    maxSparseTuples = (cacheSize/sizeof(struct ramNodeID))+1;
     
     allocStrategy = strategy;
     scale = fixpointscale;