diff --git a/tools/db_bench_tool.cc b/tools/db_bench_tool.cc
index dd5587e75..e4f07f290 100644
--- a/tools/db_bench_tool.cc
+++ b/tools/db_bench_tool.cc
@@ -1410,6 +1410,7 @@ DEFINE_int32(skip_list_lookahead, 0, "Used with skip_list memtablerep; try "
              "position");
 DEFINE_bool(report_file_operations, false, "if report number of file "
             "operations");
+DEFINE_bool(report_open_timing, false, "if report open timing");
 DEFINE_int32(readahead_size, 0, "Iterator readahead size");
 
 DEFINE_bool(read_with_latest_user_timestamp, true,
@@ -4401,6 +4402,7 @@ class Benchmark {
 
   void OpenDb(Options options, const std::string& db_name,
       DBWithColumnFamilies* db) {
+    uint64_t open_start = FLAGS_report_open_timing ? FLAGS_env->NowNanos() : 0;
     Status s;
     // Open with column families if necessary.
     if (FLAGS_num_column_families > 1) {
@@ -4541,6 +4543,11 @@ class Benchmark {
     } else {
       s = DB::Open(options, db_name, &db->db);
     }
+    if (FLAGS_report_open_timing) {
+      std::cout << "OpenDb:     "
+                << (FLAGS_env->NowNanos() - open_start) / 1000000.0
+                << " milliseconds\n";
+    }
     if (!s.ok()) {
       fprintf(stderr, "open error: %s\n", s.ToString().c_str());
       exit(1);