Adjust benchmark framework to avoid spending 50% of time on 'new Date'

test/js-perf-test/base.js

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 
 // Performance.now is used in latency benchmarks, the fallback is Date.now.
 var performance = performance || {};
 performance.now = (function() {
   return performance.now       ||
          performance.mozNow    ||
@@ skipping 263 matching lines @@
                         : benchmark.doDeterministic;
 
   function Measure(data) {
     var elapsed = 0;
     var start = new Date();
 
   // Run either for 1 second or for the number of iterations specified
   // by minIterations, depending on the config flag doDeterministic.
     for (var i = 0; (doDeterministic ?
       i<benchmark.deterministicIterations : elapsed < 1000); i++) {
-      benchmark.run();
+      for (var j = 0; j < 100; j++) benchmark.run();
       elapsed = new Date() - start;
     }
     if (data != null) {
-      data.runs += i;
+      data.hectoruns += i;
       data.elapsed += elapsed;
     }
   }
 
   // Sets up data in order to skip or not the warmup phase.
   if (!doWarmup && data == null) {
-    data = { runs: 0, elapsed: 0 };
+    data = { hectoruns: 0, elapsed: 0 };
   }
 
   if (data == null) {
     Measure(null);
-    return { runs: 0, elapsed: 0 };
+    return { hectoruns: 0, elapsed: 0 };
   } else {
     Measure(data);
     // If we've run too few iterations, we continue for another second.
-    if (data.runs < benchmark.minIterations) return data;
-    var usec = (data.elapsed * 1000) / data.runs;
+    if (data.hectoruns * 100 < benchmark.minIterations) return data;
+    var usec = (data.elapsed * 10) / data.hectoruns;
     var rms = (benchmark.rmsResult != null) ? benchmark.rmsResult() : 0;
     this.NotifyStep(new BenchmarkResult(benchmark, usec, rms));
     return null;
   }
 }
 
 
 // This function starts running a suite, but stops between each
 // individual benchmark in the suite and returns a continuation
 // function which can be invoked to run the next benchmark. Once the
@@ skipping 42 matching lines @@
     } catch (e) {
       suite.NotifyError(e);
       return null;
     }
     return RunNextSetup;
   }
 
   // Start out running the setup.
   return RunNextSetup();
 }