| // 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. |
| |
| #ifndef V8_HEAP_GC_TRACER_H_ |
| #define V8_HEAP_GC_TRACER_H_ |
| |
| #include "src/base/platform/platform.h" |
| #include "src/globals.h" |
| |
| namespace v8 { |
| namespace internal { |
| |
| // A simple ring buffer class with maximum size known at compile time. |
| // The class only implements the functionality required in GCTracer. |
| template <typename T, size_t MAX_SIZE> |
| class RingBuffer { |
| public: |
| class const_iterator { |
| public: |
| const_iterator() : index_(0), elements_(NULL) {} |
| |
| const_iterator(size_t index, const T* elements) |
| : index_(index), elements_(elements) {} |
| |
| bool operator==(const const_iterator& rhs) const { |
| return elements_ == rhs.elements_ && index_ == rhs.index_; |
| } |
| |
| bool operator!=(const const_iterator& rhs) const { |
| return elements_ != rhs.elements_ || index_ != rhs.index_; |
| } |
| |
| operator const T*() const { return elements_ + index_; } |
| |
| const T* operator->() const { return elements_ + index_; } |
| |
| const T& operator*() const { return elements_[index_]; } |
| |
| const_iterator& operator++() { |
| index_ = (index_ + 1) % (MAX_SIZE + 1); |
| return *this; |
| } |
| |
| const_iterator& operator--() { |
| index_ = (index_ + MAX_SIZE) % (MAX_SIZE + 1); |
| return *this; |
| } |
| |
| private: |
| size_t index_; |
| const T* elements_; |
| }; |
| |
| RingBuffer() : begin_(0), end_(0) {} |
| |
| bool empty() const { return begin_ == end_; } |
| size_t size() const { |
| return (end_ - begin_ + MAX_SIZE + 1) % (MAX_SIZE + 1); |
| } |
| const_iterator begin() const { return const_iterator(begin_, elements_); } |
| const_iterator end() const { return const_iterator(end_, elements_); } |
| const_iterator back() const { return --end(); } |
| void push_back(const T& element) { |
| elements_[end_] = element; |
| end_ = (end_ + 1) % (MAX_SIZE + 1); |
| if (end_ == begin_) begin_ = (begin_ + 1) % (MAX_SIZE + 1); |
| } |
| void push_front(const T& element) { |
| begin_ = (begin_ + MAX_SIZE) % (MAX_SIZE + 1); |
| if (begin_ == end_) end_ = (end_ + MAX_SIZE) % (MAX_SIZE + 1); |
| elements_[begin_] = element; |
| } |
| |
| void reset() { |
| begin_ = 0; |
| end_ = 0; |
| } |
| |
| private: |
| T elements_[MAX_SIZE + 1]; |
| size_t begin_; |
| size_t end_; |
| |
| DISALLOW_COPY_AND_ASSIGN(RingBuffer); |
| }; |
| |
| |
| enum ScavengeSpeedMode { kForAllObjects, kForSurvivedObjects }; |
| |
| |
| // GCTracer collects and prints ONE line after each garbage collector |
| // invocation IFF --trace_gc is used. |
| // TODO(ernstm): Unit tests. |
| class GCTracer { |
| public: |
| class Scope { |
| public: |
| enum ScopeId { |
| EXTERNAL, |
| MC_CLEAR, |
| MC_CLEAR_CODE_FLUSH, |
| MC_CLEAR_DEPENDENT_CODE, |
| MC_CLEAR_GLOBAL_HANDLES, |
| MC_CLEAR_MAPS, |
| MC_CLEAR_SLOTS_BUFFER, |
| MC_CLEAR_STORE_BUFFER, |
| MC_CLEAR_STRING_TABLE, |
| MC_CLEAR_WEAK_CELLS, |
| MC_CLEAR_WEAK_COLLECTIONS, |
| MC_CLEAR_WEAK_LISTS, |
| MC_EVACUATE, |
| MC_EVACUATE_CANDIDATES, |
| MC_EVACUATE_CLEAN_UP, |
| MC_EVACUATE_NEW_SPACE, |
| MC_EVACUATE_UPDATE_POINTERS, |
| MC_EVACUATE_UPDATE_POINTERS_BETWEEN_EVACUATED, |
| MC_EVACUATE_UPDATE_POINTERS_TO_EVACUATED, |
| MC_EVACUATE_UPDATE_POINTERS_TO_NEW, |
| MC_EVACUATE_UPDATE_POINTERS_WEAK, |
| MC_FINISH, |
| MC_INCREMENTAL_FINALIZE, |
| MC_MARK, |
| MC_MARK_FINISH_INCREMENTAL, |
| MC_MARK_PREPARE_CODE_FLUSH, |
| MC_MARK_ROOTS, |
| MC_MARK_WEAK_CLOSURE, |
| MC_SWEEP, |
| MC_SWEEP_CODE, |
| MC_SWEEP_MAP, |
| MC_SWEEP_OLD, |
| SCAVENGER_CODE_FLUSH_CANDIDATES, |
| SCAVENGER_OBJECT_GROUPS, |
| SCAVENGER_OLD_TO_NEW_POINTERS, |
| SCAVENGER_ROOTS, |
| SCAVENGER_SCAVENGE, |
| SCAVENGER_SEMISPACE, |
| SCAVENGER_WEAK, |
| NUMBER_OF_SCOPES |
| }; |
| |
| Scope(GCTracer* tracer, ScopeId scope); |
| ~Scope(); |
| |
| private: |
| GCTracer* tracer_; |
| ScopeId scope_; |
| double start_time_; |
| |
| DISALLOW_COPY_AND_ASSIGN(Scope); |
| }; |
| |
| |
| class AllocationEvent { |
| public: |
| // Default constructor leaves the event uninitialized. |
| AllocationEvent() {} |
| |
| AllocationEvent(double duration, size_t allocation_in_bytes); |
| |
| // Time spent in the mutator during the end of the last sample to the |
| // beginning of the next sample. |
| double duration_; |
| |
| // Memory allocated in the new space during the end of the last sample |
| // to the beginning of the next sample |
| size_t allocation_in_bytes_; |
| }; |
| |
| |
| class CompactionEvent { |
| public: |
| CompactionEvent() : duration(0), live_bytes_compacted(0) {} |
| |
| CompactionEvent(double duration, intptr_t live_bytes_compacted) |
| : duration(duration), live_bytes_compacted(live_bytes_compacted) {} |
| |
| double duration; |
| intptr_t live_bytes_compacted; |
| }; |
| |
| |
| class ContextDisposalEvent { |
| public: |
| // Default constructor leaves the event uninitialized. |
| ContextDisposalEvent() {} |
| |
| explicit ContextDisposalEvent(double time); |
| |
| // Time when context disposal event happened. |
| double time_; |
| }; |
| |
| |
| class SurvivalEvent { |
| public: |
| // Default constructor leaves the event uninitialized. |
| SurvivalEvent() {} |
| |
| explicit SurvivalEvent(double survival_ratio); |
| |
| double promotion_ratio_; |
| }; |
| |
| |
| class Event { |
| public: |
| enum Type { |
| SCAVENGER = 0, |
| MARK_COMPACTOR = 1, |
| INCREMENTAL_MARK_COMPACTOR = 2, |
| START = 3 |
| }; |
| |
| // Default constructor leaves the event uninitialized. |
| Event() {} |
| |
| Event(Type type, const char* gc_reason, const char* collector_reason); |
| |
| // Returns a string describing the event type. |
| const char* TypeName(bool short_name) const; |
| |
| // Type of event |
| Type type; |
| |
| const char* gc_reason; |
| const char* collector_reason; |
| |
| // Timestamp set in the constructor. |
| double start_time; |
| |
| // Timestamp set in the destructor. |
| double end_time; |
| |
| // Memory reduction flag set. |
| bool reduce_memory; |
| |
| // Size of objects in heap set in constructor. |
| intptr_t start_object_size; |
| |
| // Size of objects in heap set in destructor. |
| intptr_t end_object_size; |
| |
| // Size of memory allocated from OS set in constructor. |
| intptr_t start_memory_size; |
| |
| // Size of memory allocated from OS set in destructor. |
| intptr_t end_memory_size; |
| |
| // Total amount of space either wasted or contained in one of free lists |
| // before the current GC. |
| intptr_t start_holes_size; |
| |
| // Total amount of space either wasted or contained in one of free lists |
| // after the current GC. |
| intptr_t end_holes_size; |
| |
| // Size of new space objects in constructor. |
| intptr_t new_space_object_size; |
| // Size of survived new space objects in desctructor. |
| intptr_t survived_new_space_object_size; |
| |
| // Number of incremental marking steps since creation of tracer. |
| // (value at start of event) |
| int cumulative_incremental_marking_steps; |
| |
| // Incremental marking steps since |
| // - last event for SCAVENGER events |
| // - last INCREMENTAL_MARK_COMPACTOR event for INCREMENTAL_MARK_COMPACTOR |
| // events |
| int incremental_marking_steps; |
| |
| // Bytes marked since creation of tracer (value at start of event). |
| intptr_t cumulative_incremental_marking_bytes; |
| |
| // Bytes marked since |
| // - last event for SCAVENGER events |
| // - last INCREMENTAL_MARK_COMPACTOR event for INCREMENTAL_MARK_COMPACTOR |
| // events |
| intptr_t incremental_marking_bytes; |
| |
| // Cumulative duration of incremental marking steps since creation of |
| // tracer. (value at start of event) |
| double cumulative_incremental_marking_duration; |
| |
| // Duration of incremental marking steps since |
| // - last event for SCAVENGER events |
| // - last INCREMENTAL_MARK_COMPACTOR event for INCREMENTAL_MARK_COMPACTOR |
| // events |
| double incremental_marking_duration; |
| |
| // Cumulative pure duration of incremental marking steps since creation of |
| // tracer. (value at start of event) |
| double cumulative_pure_incremental_marking_duration; |
| |
| // Duration of pure incremental marking steps since |
| // - last event for SCAVENGER events |
| // - last INCREMENTAL_MARK_COMPACTOR event for INCREMENTAL_MARK_COMPACTOR |
| // events |
| double pure_incremental_marking_duration; |
| |
| // Longest incremental marking step since start of marking. |
| // (value at start of event) |
| double longest_incremental_marking_step; |
| |
| // Amounts of time spent in different scopes during GC. |
| double scopes[Scope::NUMBER_OF_SCOPES]; |
| }; |
| |
| static const size_t kRingBufferMaxSize = 10; |
| |
| typedef RingBuffer<Event, kRingBufferMaxSize> EventBuffer; |
| |
| typedef RingBuffer<AllocationEvent, kRingBufferMaxSize> AllocationEventBuffer; |
| |
| typedef RingBuffer<ContextDisposalEvent, kRingBufferMaxSize> |
| ContextDisposalEventBuffer; |
| |
| typedef RingBuffer<CompactionEvent, kRingBufferMaxSize> CompactionEventBuffer; |
| |
| typedef RingBuffer<SurvivalEvent, kRingBufferMaxSize> SurvivalEventBuffer; |
| |
| static const int kThroughputTimeFrameMs = 5000; |
| |
| explicit GCTracer(Heap* heap); |
| |
| // Start collecting data. |
| void Start(GarbageCollector collector, const char* gc_reason, |
| const char* collector_reason); |
| |
| // Stop collecting data and print results. |
| void Stop(GarbageCollector collector); |
| |
| // Sample and accumulate bytes allocated since the last GC. |
| void SampleAllocation(double current_ms, size_t new_space_counter_bytes, |
| size_t old_generation_counter_bytes); |
| |
| // Log the accumulated new space allocation bytes. |
| void AddAllocation(double current_ms); |
| |
| void AddContextDisposalTime(double time); |
| |
| void AddCompactionEvent(double duration, intptr_t live_bytes_compacted); |
| |
| void AddSurvivalRatio(double survival_ratio); |
| |
| // Log an incremental marking step. |
| void AddIncrementalMarkingStep(double duration, intptr_t bytes); |
| |
| void AddIncrementalMarkingFinalizationStep(double duration); |
| |
| // Log time spent in marking. |
| void AddMarkingTime(double duration) { |
| cumulative_marking_duration_ += duration; |
| } |
| |
| // Time spent in marking. |
| double cumulative_marking_duration() const { |
| return cumulative_marking_duration_; |
| } |
| |
| // Log time spent in sweeping on main thread. |
| void AddSweepingTime(double duration) { |
| cumulative_sweeping_duration_ += duration; |
| } |
| |
| // Time spent in sweeping on main thread. |
| double cumulative_sweeping_duration() const { |
| return cumulative_sweeping_duration_; |
| } |
| |
| // Compute the mean duration of the last scavenger events. Returns 0 if no |
| // events have been recorded. |
| double MeanScavengerDuration() const { |
| return MeanDuration(scavenger_events_); |
| } |
| |
| // Compute the max duration of the last scavenger events. Returns 0 if no |
| // events have been recorded. |
| double MaxScavengerDuration() const { return MaxDuration(scavenger_events_); } |
| |
| // Compute the mean duration of the last mark compactor events. Returns 0 if |
| // no events have been recorded. |
| double MeanMarkCompactorDuration() const { |
| return MeanDuration(mark_compactor_events_); |
| } |
| |
| // Compute the max duration of the last mark compactor events. Return 0 if no |
| // events have been recorded. |
| double MaxMarkCompactorDuration() const { |
| return MaxDuration(mark_compactor_events_); |
| } |
| |
| // Compute the mean duration of the last incremental mark compactor |
| // events. Returns 0 if no events have been recorded. |
| double MeanIncrementalMarkCompactorDuration() const { |
| return MeanDuration(incremental_mark_compactor_events_); |
| } |
| |
| // Compute the mean step duration of the last incremental marking round. |
| // Returns 0 if no incremental marking round has been completed. |
| double MeanIncrementalMarkingDuration() const; |
| |
| // Compute the max step duration of the last incremental marking round. |
| // Returns 0 if no incremental marking round has been completed. |
| double MaxIncrementalMarkingDuration() const; |
| |
| // Compute the average incremental marking speed in bytes/millisecond. |
| // Returns 0 if no events have been recorded. |
| intptr_t IncrementalMarkingSpeedInBytesPerMillisecond() const; |
| |
| // Compute the average scavenge speed in bytes/millisecond. |
| // Returns 0 if no events have been recorded. |
| intptr_t ScavengeSpeedInBytesPerMillisecond( |
| ScavengeSpeedMode mode = kForAllObjects) const; |
| |
| // Compute the average compaction speed in bytes/millisecond. |
| // Returns 0 if not enough events have been recorded. |
| intptr_t CompactionSpeedInBytesPerMillisecond() const; |
| |
| // Compute the average mark-sweep speed in bytes/millisecond. |
| // Returns 0 if no events have been recorded. |
| intptr_t MarkCompactSpeedInBytesPerMillisecond() const; |
| |
| // Compute the average incremental mark-sweep finalize speed in |
| // bytes/millisecond. |
| // Returns 0 if no events have been recorded. |
| intptr_t FinalIncrementalMarkCompactSpeedInBytesPerMillisecond() const; |
| |
| // Compute the overall mark compact speed including incremental steps |
| // and the final mark-compact step. |
| double CombinedMarkCompactSpeedInBytesPerMillisecond(); |
| |
| // Allocation throughput in the new space in bytes/millisecond. |
| // Returns 0 if no allocation events have been recorded. |
| size_t NewSpaceAllocationThroughputInBytesPerMillisecond( |
| double time_ms = 0) const; |
| |
| // Allocation throughput in the old generation in bytes/millisecond in the |
| // last time_ms milliseconds. |
| // Returns 0 if no allocation events have been recorded. |
| size_t OldGenerationAllocationThroughputInBytesPerMillisecond( |
| double time_ms = 0) const; |
| |
| // Allocation throughput in heap in bytes/millisecond in the last time_ms |
| // milliseconds. |
| // Returns 0 if no allocation events have been recorded. |
| size_t AllocationThroughputInBytesPerMillisecond(double time_ms) const; |
| |
| // Allocation throughput in heap in bytes/milliseconds in the last |
| // kThroughputTimeFrameMs seconds. |
| // Returns 0 if no allocation events have been recorded. |
| size_t CurrentAllocationThroughputInBytesPerMillisecond() const; |
| |
| // Allocation throughput in old generation in bytes/milliseconds in the last |
| // kThroughputTimeFrameMs seconds. |
| // Returns 0 if no allocation events have been recorded. |
| size_t CurrentOldGenerationAllocationThroughputInBytesPerMillisecond() const; |
| |
| // Computes the context disposal rate in milliseconds. It takes the time |
| // frame of the first recorded context disposal to the current time and |
| // divides it by the number of recorded events. |
| // Returns 0 if no events have been recorded. |
| double ContextDisposalRateInMilliseconds() const; |
| |
| // Computes the average survival ratio based on the last recorded survival |
| // events. |
| // Returns 0 if no events have been recorded. |
| double AverageSurvivalRatio() const; |
| |
| // Returns true if at least one survival event was recorded. |
| bool SurvivalEventsRecorded() const; |
| |
| // Discard all recorded survival events. |
| void ResetSurvivalEvents(); |
| |
| private: |
| // Print one detailed trace line in name=value format. |
| // TODO(ernstm): Move to Heap. |
| void PrintNVP() const; |
| |
| // Print one trace line. |
| // TODO(ernstm): Move to Heap. |
| void Print() const; |
| |
| // Prints a line and also adds it to the heap's ring buffer so that |
| // it can be included in later crash dumps. |
| void Output(const char* format, ...) const; |
| |
| // Compute the mean duration of the events in the given ring buffer. |
| double MeanDuration(const EventBuffer& events) const; |
| |
| // Compute the max duration of the events in the given ring buffer. |
| double MaxDuration(const EventBuffer& events) const; |
| |
| void ClearMarkCompactStatistics() { |
| cumulative_incremental_marking_steps_ = 0; |
| cumulative_incremental_marking_bytes_ = 0; |
| cumulative_incremental_marking_duration_ = 0; |
| cumulative_pure_incremental_marking_duration_ = 0; |
| longest_incremental_marking_step_ = 0; |
| cumulative_incremental_marking_finalization_steps_ = 0; |
| cumulative_incremental_marking_finalization_duration_ = 0; |
| longest_incremental_marking_finalization_step_ = 0; |
| cumulative_marking_duration_ = 0; |
| cumulative_sweeping_duration_ = 0; |
| } |
| |
| // Pointer to the heap that owns this tracer. |
| Heap* heap_; |
| |
| // Current tracer event. Populated during Start/Stop cycle. Valid after Stop() |
| // has returned. |
| Event current_; |
| |
| // Previous tracer event. |
| Event previous_; |
| |
| // Previous INCREMENTAL_MARK_COMPACTOR event. |
| Event previous_incremental_mark_compactor_event_; |
| |
| // RingBuffers for SCAVENGER events. |
| EventBuffer scavenger_events_; |
| |
| // RingBuffers for MARK_COMPACTOR events. |
| EventBuffer mark_compactor_events_; |
| |
| // RingBuffers for INCREMENTAL_MARK_COMPACTOR events. |
| EventBuffer incremental_mark_compactor_events_; |
| |
| // RingBuffer for allocation events. |
| AllocationEventBuffer new_space_allocation_events_; |
| AllocationEventBuffer old_generation_allocation_events_; |
| |
| // RingBuffer for context disposal events. |
| ContextDisposalEventBuffer context_disposal_events_; |
| |
| // RingBuffer for compaction events. |
| CompactionEventBuffer compaction_events_; |
| |
| // RingBuffer for survival events. |
| SurvivalEventBuffer survival_events_; |
| |
| // Cumulative number of incremental marking steps since creation of tracer. |
| int cumulative_incremental_marking_steps_; |
| |
| // Cumulative size of incremental marking steps (in bytes) since creation of |
| // tracer. |
| intptr_t cumulative_incremental_marking_bytes_; |
| |
| // Cumulative duration of incremental marking steps since creation of tracer. |
| double cumulative_incremental_marking_duration_; |
| |
| // Cumulative duration of pure incremental marking steps since creation of |
| // tracer. |
| double cumulative_pure_incremental_marking_duration_; |
| |
| // Longest incremental marking step since start of marking. |
| double longest_incremental_marking_step_; |
| |
| // Cumulative number of incremental marking finalization steps since creation |
| // of tracer. |
| int cumulative_incremental_marking_finalization_steps_; |
| |
| // Cumulative duration of incremental marking finalization steps since |
| // creation of tracer. |
| double cumulative_incremental_marking_finalization_duration_; |
| |
| // Longest incremental marking finalization step since start of marking. |
| double longest_incremental_marking_finalization_step_; |
| |
| // Total marking time. |
| // This timer is precise when run with --print-cumulative-gc-stat |
| double cumulative_marking_duration_; |
| |
| // Total sweeping time on the main thread. |
| // This timer is precise when run with --print-cumulative-gc-stat |
| // TODO(hpayer): Account for sweeping time on sweeper threads. Add a |
| // different field for that. |
| // TODO(hpayer): This timer right now just holds the sweeping time |
| // of the initial atomic sweeping pause. Make sure that it accumulates |
| // all sweeping operations performed on the main thread. |
| double cumulative_sweeping_duration_; |
| |
| // Timestamp and allocation counter at the last sampled allocation event. |
| double allocation_time_ms_; |
| size_t new_space_allocation_counter_bytes_; |
| size_t old_generation_allocation_counter_bytes_; |
| |
| // Accumulated duration and allocated bytes since the last GC. |
| double allocation_duration_since_gc_; |
| size_t new_space_allocation_in_bytes_since_gc_; |
| size_t old_generation_allocation_in_bytes_since_gc_; |
| |
| double combined_mark_compact_speed_cache_; |
| |
| // Counts how many tracers were started without stopping. |
| int start_counter_; |
| |
| DISALLOW_COPY_AND_ASSIGN(GCTracer); |
| }; |
| } // namespace internal |
| } // namespace v8 |
| |
| #endif // V8_HEAP_GC_TRACER_H_ |