Sampling heap profiler: Force Full GC before retrieving the profile.

include/v8-profiler.h

 // Copyright 2010 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.
 
 #ifndef V8_V8_PROFILER_H_
 #define V8_V8_PROFILER_H_
 
 #include <vector>
 #include "v8.h"  // NOLINT(build/include)
 
@@ skipping 497 matching lines @@
   static const int kNoColumnNumberInfo = Message::kNoColumnInfo;
 };
 
 
 /**
  * Interface for controlling heap profiling. Instance of the
  * profiler can be retrieved using v8::Isolate::GetHeapProfiler.
  */
 class V8_EXPORT HeapProfiler {
  public:
+  enum SamplingFlags {
+    kSamplingNoFlags = 0,
+    kSamplingForceGC = 1 << 0,

[ulan, 2016/05/04 13:13:06]

To be more descriptive, maybe kSamplingForceGCAtAllocationProfile or something
similar?

[alph, 2016/05/04 18:40:16]

Don't think we should go into implementation details here.

+  };
+
   /**
    * Callback function invoked for obtaining RetainedObjectInfo for
    * the given JavaScript wrapper object. It is prohibited to enter V8
    * while the callback is running: only getters on the handle and
    * GetPointerFromInternalField on the objects are allowed.
    */
   typedef RetainedObjectInfo* (*WrapperInfoCallback)(uint16_t class_id,
                                                      Local<Value> wrapper);
 
   /** Returns the number of snapshots taken. */
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    * newspace allocations. Support for paged space allocation (e.g. pre-tenured
    * objects, large objects, code objects, etc.) and native allocations
    * doesn't exist yet, but is anticipated in the future.
    *
    * Objects allocated before the sampling is started will not be included in
    * the profile.
    *
    * Returns false if a sampling heap profiler is already running.
    */
   bool StartSamplingHeapProfiler(uint64_t sample_interval = 512 * 1024,
-                                 int stack_depth = 16);
+                                 int stack_depth = 16,
+                                 SamplingFlags flags = kSamplingNoFlags);
 
   /**
    * Stops the sampling heap profile and discards the current profile.
    */
   void StopSamplingHeapProfiler();
 
   /**
    * Returns the sampled profile of allocations allocated (and still live) since
    * StartSamplingHeapProfiler was called. The ownership of the pointer is
    * transfered to the caller. Returns nullptr if sampling heap profiler is not
@@ skipping 119 matching lines @@
   uint32_t index;  // Index of the time interval that was changed.
   uint32_t count;  // New value of count field for the interval with this index.
   uint32_t size;  // New value of size field for the interval with this index.
 };
 
 
 }  // namespace v8
 
 
 #endif  // V8_V8_PROFILER_H_