v8-metrics.h

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// Copyright 2020 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_METRICS_H_
#define V8_METRICS_H_
 
#include <stddef.h>
#include <stdint.h>
 
#include <optional>
#include <vector>
 
#include "v8-internal.h"      // NOLINT(build/include_directory)
#include "v8-isolate.h"       // NOLINT(build/include_directory)
#include "v8-local-handle.h"  // NOLINT(build/include_directory)
#include "v8config.h"         // NOLINT(build/include_directory)
 
namespace v8 {
 
class Context;
class Isolate;
 
namespace metrics {
 
struct GarbageCollectionPhases {
  int64_t total_wall_clock_duration_in_us = -1;
  int64_t compact_wall_clock_duration_in_us = -1;
  int64_t mark_wall_clock_duration_in_us = -1;
  int64_t sweep_wall_clock_duration_in_us = -1;
  int64_t weak_wall_clock_duration_in_us = -1;
};
 
struct GarbageCollectionSizes {
  int64_t bytes_before = -1;
  int64_t bytes_after = -1;
  int64_t bytes_freed = -1;
};
 
struct GarbageCollectionLimits {
  int64_t bytes_baseline = -1;
  int64_t bytes_limit = -1;
  int64_t bytes_current = -1;
  int64_t bytes_max = -1;
};
 
struct GarbageCollectionFullCycle {
  int reason = -1;
  int incremental_marking_reason = -1;
  // The priority of the isolate during the GC cycle. A nullopt value denotes a
  // mixed priority cycle, meaning the Isolate's priority was changed while the
  // cycle was in progress.
  std::optional<v8::Isolate::Priority> priority = std::nullopt;
  bool reduce_memory = false;
  bool is_loading = false;
  GarbageCollectionPhases total;
  GarbageCollectionPhases total_cpp;
  GarbageCollectionPhases main_thread;
  GarbageCollectionPhases main_thread_cpp;
  GarbageCollectionPhases main_thread_atomic;
  GarbageCollectionPhases main_thread_atomic_cpp;
  GarbageCollectionPhases main_thread_incremental;
  GarbageCollectionPhases main_thread_incremental_cpp;
  GarbageCollectionSizes objects;
  GarbageCollectionSizes objects_cpp;
  GarbageCollectionSizes memory;
  GarbageCollectionSizes memory_cpp;
  GarbageCollectionLimits old_generation_consumed;
  GarbageCollectionLimits global_consumed;
  int64_t external_memory_bytes = -1;
  double collection_rate_in_percent = -1.0;
  double collection_rate_cpp_in_percent = -1.0;
  double efficiency_in_bytes_per_us = -1.0;
  double efficiency_cpp_in_bytes_per_us = -1.0;
  double main_thread_efficiency_in_bytes_per_us = -1.0;
  double main_thread_efficiency_cpp_in_bytes_per_us = -1.0;
  double collection_weight_in_percent = -1.0;
  double collection_weight_cpp_in_percent = -1.0;
  double main_thread_collection_weight_in_percent = -1.0;
  double main_thread_collection_weight_cpp_in_percent = -1.0;
  int64_t incremental_marking_start_stop_wall_clock_duration_in_us = -1;
  int64_t total_duration_since_last_mark_compact = -1;
};
 
struct GarbageCollectionFullMainThreadIncrementalMark {
  int64_t wall_clock_duration_in_us = -1;
  int64_t cpp_wall_clock_duration_in_us = -1;
};
 
struct GarbageCollectionFullMainThreadIncrementalSweep {
  int64_t wall_clock_duration_in_us = -1;
  int64_t cpp_wall_clock_duration_in_us = -1;
};
 
template <typename EventType>
struct GarbageCollectionBatchedEvents {
  std::vector<EventType> events;
};
 
using GarbageCollectionFullMainThreadBatchedIncrementalMark =
    GarbageCollectionBatchedEvents<
        GarbageCollectionFullMainThreadIncrementalMark>;
using GarbageCollectionFullMainThreadBatchedIncrementalSweep =
    GarbageCollectionBatchedEvents<
        GarbageCollectionFullMainThreadIncrementalSweep>;
 
struct GarbageCollectionYoungCycle {
  int reason = -1;
  // The priority of the isolate during the GC cycle. A nullopt value denotes a
  // mixed priority cycle, meaning the Isolate's priority was changed while the
  // cycle was in progress.
  std::optional<v8::Isolate::Priority> priority = std::nullopt;
  int64_t total_wall_clock_duration_in_us = -1;
  int64_t main_thread_wall_clock_duration_in_us = -1;
  double collection_rate_in_percent = -1.0;
  double efficiency_in_bytes_per_us = -1.0;
  double main_thread_efficiency_in_bytes_per_us = -1.0;
#if defined(CPPGC_YOUNG_GENERATION)
  GarbageCollectionPhases total_cpp;
  GarbageCollectionSizes objects_cpp;
  GarbageCollectionSizes memory_cpp;
  double collection_rate_cpp_in_percent = -1.0;
  double efficiency_cpp_in_bytes_per_us = -1.0;
  double main_thread_efficiency_cpp_in_bytes_per_us = -1.0;
#endif  // defined(CPPGC_YOUNG_GENERATION)
};
 
// Note: These structs do not define any constructor, and declare most fields as
// const, to force initializing them when using aggregate (designated)
// initialization.
// Those structs are meant to be created in V8 and read by embedders.
struct WasmModuleDecoded {
  const bool async;
  const bool streamed;
  const bool success;
  const size_t module_size_in_bytes;
  const size_t function_count;
  // Optional field; only set if a high-resolution clock is available.
  int64_t wall_clock_duration_in_us = -1;
};
 
struct WasmModuleCompiled {
  const bool async;
  const bool streamed;
  const bool cached;
  const bool deserialized;
  const bool lazy;
  const bool success;
  const size_t code_size_in_bytes;
  const size_t liftoff_bailout_count;
  // Optional field; only set if a high-resolution clock is available.
  int64_t wall_clock_duration_in_us = -1;
};
 
struct WasmModuleInstantiated {
  const bool async;
  const bool success;
  const size_t imported_function_count;
  // Optional field; only set if a high-resolution clock is available.
  int64_t wall_clock_duration_in_us = -1;
};
 
struct WasmModulesPerIsolate {
  const size_t count;
};
 
class V8_EXPORT Recorder {
 public:
  // A unique identifier for a context in this Isolate.
  // It is guaranteed to not be reused throughout the lifetime of the Isolate.
  class ContextId {
   public:
    ContextId() : id_(kEmptyId) {}
 
    bool IsEmpty() const { return id_ == kEmptyId; }
    static const ContextId Empty() { return ContextId{kEmptyId}; }
 
    bool operator==(const ContextId& other) const { return id_ == other.id_; }
    bool operator!=(const ContextId& other) const { return id_ != other.id_; }
 
   private:
    friend class ::v8::Context;
    friend class ::v8::internal::Isolate;
 
    explicit ContextId(uintptr_t id) : id_(id) {}
 
    static constexpr uintptr_t kEmptyId = 0;
    uintptr_t id_;
  };
 
  virtual ~Recorder() = default;
 
  // Main thread events. Those are only triggered on the main thread, and hence
  // can access the context.
#define ADD_MAIN_THREAD_EVENT(E) \
  virtual void AddMainThreadEvent(const E&, ContextId) {}
  ADD_MAIN_THREAD_EVENT(GarbageCollectionFullCycle)
  ADD_MAIN_THREAD_EVENT(GarbageCollectionFullMainThreadIncrementalMark)
  ADD_MAIN_THREAD_EVENT(GarbageCollectionFullMainThreadBatchedIncrementalMark)
  ADD_MAIN_THREAD_EVENT(GarbageCollectionFullMainThreadIncrementalSweep)
  ADD_MAIN_THREAD_EVENT(GarbageCollectionFullMainThreadBatchedIncrementalSweep)
  ADD_MAIN_THREAD_EVENT(GarbageCollectionYoungCycle)
  ADD_MAIN_THREAD_EVENT(WasmModuleDecoded)
  ADD_MAIN_THREAD_EVENT(WasmModuleCompiled)
  ADD_MAIN_THREAD_EVENT(WasmModuleInstantiated)
#undef ADD_MAIN_THREAD_EVENT
 
  // Thread-safe events are not allowed to access the context and therefore do
  // not carry a context ID with them. These IDs can be generated using
  // Recorder::GetContextId() and the ID will be valid throughout the lifetime
  // of the isolate. It is not guaranteed that the ID will still resolve to
  // a valid context using Recorder::GetContext() at the time the metric is
  // recorded. In this case, an empty handle will be returned.
#define ADD_THREAD_SAFE_EVENT(E) \
  virtual void AddThreadSafeEvent(const E&) {}
  ADD_THREAD_SAFE_EVENT(WasmModulesPerIsolate)
#undef ADD_THREAD_SAFE_EVENT
 
  virtual void NotifyIsolateDisposal() {}
 
  // Return the context with the given id or an empty handle if the context
  // was already garbage collected.
  static MaybeLocal<Context> GetContext(Isolate* isolate, ContextId id);
  // Return the unique id corresponding to the given context.
  static ContextId GetContextId(Local<Context> context);
};
 
struct V8_EXPORT LongTaskStats {
  V8_INLINE static void Reset(Isolate* isolate) {
    v8::internal::Internals::IncrementLongTasksStatsCounter(isolate);
  }
 
  static LongTaskStats Get(Isolate* isolate);
 
  int64_t gc_full_atomic_wall_clock_duration_us = 0;
  int64_t gc_full_incremental_wall_clock_duration_us = 0;
  int64_t gc_young_wall_clock_duration_us = 0;
  // Only collected with --slow-histograms
  int64_t v8_execute_us = 0;
};
 
}  // namespace metrics
}  // namespace v8
 
#endif  // V8_METRICS_H_