diff --git a/tools/blob_store_bench.cc b/tools/blob_store_bench.cc
index 0d0751ead..6bedcb06f 100644
--- a/tools/blob_store_bench.cc
+++ b/tools/blob_store_bench.cc
@@ -8,6 +8,10 @@
 
 #define KB 1024LL
 #define MB 1024*1024LL
+// BlobStore does costly asserts to make sure it's running correctly, which
+// significantly impacts benchmark runtime.
+// NDEBUG will compile out those asserts.
+#define NDEBUG
 
 using namespace rocksdb;
 using namespace std;