[vm service] Collect garbage before getting native allocation samples

runtime/vm/service.cc

 // Copyright (c) 2013, 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/service.h"
 
 #include "include/dart_api.h"
 #include "include/dart_native_api.h"
 #include "platform/globals.h"
 
@@ skipping 3247 matching lines @@
 };
 
 
 static bool GetNativeAllocationSamples(Thread* thread, JSONStream* js) {
   Profile::TagOrder tag_order =
       EnumMapper(js->LookupParam("tags"), tags_enum_names, tags_enum_values);
   int64_t time_origin_micros =
       Int64Parameter::Parse(js->LookupParam("timeOriginMicros"));
   int64_t time_extent_micros =
       Int64Parameter::Parse(js->LookupParam("timeExtentMicros"));
+#if defined(DEBUG)
+  Isolate::Current()->heap()->CollectAllGarbage();
+#endif
   ProfilerService::PrintNativeAllocationJSON(js, tag_order, time_origin_micros,
                                              time_extent_micros);
   return true;
 }
 
 
 static const MethodParameter* clear_cpu_profile_params[] = {
     RUNNABLE_ISOLATE_PARAMETER, NULL,
 };
 
@@ skipping 36 matching lines @@
   }
   if (should_collect) {
     isolate->UpdateLastAllocationProfileGCTimestamp();
     isolate->heap()->CollectAllGarbage();
   }
   isolate->class_table()->AllocationProfilePrintJSON(js);
   return true;
 }
 
 
+static const MethodParameter* collect_all_garbage_params[] = {
+    RUNNABLE_ISOLATE_PARAMETER, NULL,
+};
+
+#if defined(DEBUG)
+static bool CollectAllGarbage(Thread* thread, JSONStream* js) {
+  Isolate* isolate = thread->isolate();
+  isolate->heap()->CollectAllGarbage();
+  PrintSuccess(js);
+  return true;
+}
+#else
+static bool CollectAllGarbage(Thread* thread, JSONStream* js) {
+  PrintSuccess(js);
+  return true;
+}
+#endif  // defined(DEBUG)
+
+
 static const MethodParameter* get_heap_map_params[] = {
     RUNNABLE_ISOLATE_PARAMETER, NULL,
 };
 
 
 static bool GetHeapMap(Thread* thread, JSONStream* js) {
   Isolate* isolate = thread->isolate();
   isolate->heap()->PrintHeapMapToJSONStream(isolate, js);
   return true;
 }
@@ skipping 829 matching lines @@
   { "setLibraryDebuggable", SetLibraryDebuggable,
     set_library_debuggable_params },
   { "setName", SetName,
     set_name_params },
   { "_setTraceClassAllocation", SetTraceClassAllocation,
     set_trace_class_allocation_params },
   { "setVMName", SetVMName,
     set_vm_name_params },
   { "_setVMTimelineFlags", SetVMTimelineFlags,
     set_vm_timeline_flags_params },
+  { "_collectAllGarbage", CollectAllGarbage,
+    collect_all_garbage_params },
 };
 // clang-format on
 
 const ServiceMethodDescriptor* FindMethod(const char* method_name) {
   intptr_t num_methods = sizeof(service_methods_) / sizeof(service_methods_[0]);
   for (intptr_t i = 0; i < num_methods; i++) {
     const ServiceMethodDescriptor& method = service_methods_[i];
     if (strcmp(method_name, method.name) == 0) {
       return &method;
     }
   }
   return NULL;
 }
 
 #endif  // !PRODUCT
 
 }  // namespace dart