Use list of isolates in profiler

runtime/vm/benchmark_test.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/benchmark_test.h"
 
 #include "bin/builtin.h"
 #include "bin/file.h"
 
 #include "platform/assert.h"
@@ skipping 464 matching lines @@
   Dart_Handle lib = TestCase::LoadTestScript(kScriptChars, NULL);
 
   Timer timer(true, "currentMirrorSystem() benchmark");
   timer.Start();
   Dart_Invoke(lib, NewString("benchmark"), 0, NULL);
   timer.Stop();
   int64_t elapsed_time = timer.TotalElapsedTime();
   benchmark->set_score(elapsed_time);
 }
 
+
+BENCHMARK(EnterExitIsolate) {
+  const char* kScriptChars =
+      "import 'dart:core';\n"
+      "\n";
+  const intptr_t kLoopCount = 1000000;
+  TestCase::LoadTestScript(kScriptChars, NULL);
+  Api::CheckIsolateState(Isolate::Current());
+  Dart_Isolate isolate = Dart_CurrentIsolate();
+  Timer timer(true, "Enter and Exit isolate");
+  timer.Start();
+  for (intptr_t i = 0; i < kLoopCount; i++) {
+    Dart_ExitIsolate();
+    Dart_EnterIsolate(isolate);
+  }
+  timer.Stop();
+  int64_t elapsed_time = timer.TotalElapsedTime();
+  benchmark->set_score(elapsed_time);
+}

[siva, 2014/02/05 19:09:15]

I think we also need a benchmark to measure Creation of Isolates in order to
figure out how costly adding an Isolate to a list during creation is going to
be.

[Cutch, 2014/02/05 23:00:31]

With a linked list approach the only bottleneck will be contention from creating
isolates on different threads. We already track single isolate startup time so
adding another benchmark probably isn't worth it.

+
 }  // namespace dart