| /* |
| * Copyright (C) 2008 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #ifndef ART_RUNTIME_GC_HEAP_H_ |
| #define ART_RUNTIME_GC_HEAP_H_ |
| |
| #include <iosfwd> |
| #include <string> |
| #include <vector> |
| |
| #include "atomic_integer.h" |
| #include "base/timing_logger.h" |
| #include "gc/accounting/atomic_stack.h" |
| #include "gc/accounting/card_table.h" |
| #include "gc/collector/gc_type.h" |
| #include "globals.h" |
| #include "gtest/gtest.h" |
| #include "jni.h" |
| #include "locks.h" |
| #include "offsets.h" |
| #include "safe_map.h" |
| #include "thread_pool.h" |
| |
| namespace art { |
| |
| class ConditionVariable; |
| class Mutex; |
| class StackVisitor; |
| class Thread; |
| class TimingLogger; |
| |
| namespace mirror { |
| class Class; |
| class Object; |
| } // namespace mirror |
| |
| namespace gc { |
| namespace accounting { |
| class HeapBitmap; |
| class ModUnionTable; |
| class SpaceSetMap; |
| } // namespace accounting |
| |
| namespace collector { |
| class GarbageCollector; |
| class MarkSweep; |
| } // namespace collector |
| |
| namespace space { |
| class AllocSpace; |
| class DiscontinuousSpace; |
| class DlMallocSpace; |
| class ImageSpace; |
| class LargeObjectSpace; |
| class Space; |
| class SpaceTest; |
| } // namespace space |
| |
| class AgeCardVisitor { |
| public: |
| byte operator()(byte card) const { |
| if (card == accounting::CardTable::kCardDirty) { |
| return card - 1; |
| } else { |
| return 0; |
| } |
| } |
| }; |
| |
| // What caused the GC? |
| enum GcCause { |
| // GC triggered by a failed allocation. Thread doing allocation is blocked waiting for GC before |
| // retrying allocation. |
| kGcCauseForAlloc, |
| // A background GC trying to ensure there is free memory ahead of allocations. |
| kGcCauseBackground, |
| // An explicit System.gc() call. |
| kGcCauseExplicit, |
| }; |
| std::ostream& operator<<(std::ostream& os, const GcCause& policy); |
| |
| // How we want to sanity check the heap's correctness. |
| enum HeapVerificationMode { |
| kHeapVerificationNotPermitted, // Too early in runtime start-up for heap to be verified. |
| kNoHeapVerification, // Production default. |
| kVerifyAllFast, // Sanity check all heap accesses with quick(er) tests. |
| kVerifyAll // Sanity check all heap accesses. |
| }; |
| const HeapVerificationMode kDesiredHeapVerification = kNoHeapVerification; |
| |
| class Heap { |
| public: |
| static const size_t kDefaultInitialSize = 2 * MB; |
| static const size_t kDefaultMaximumSize = 32 * MB; |
| static const size_t kDefaultMaxFree = 2 * MB; |
| static const size_t kDefaultMinFree = kDefaultMaxFree / 4; |
| |
| // Default target utilization. |
| static const double kDefaultTargetUtilization; |
| |
| // Used so that we don't overflow the allocation time atomic integer. |
| static const size_t kTimeAdjust = 1024; |
| |
| // Create a heap with the requested sizes. The possible empty |
| // image_file_names names specify Spaces to load based on |
| // ImageWriter output. |
| explicit Heap(size_t initial_size, size_t growth_limit, size_t min_free, |
| size_t max_free, double target_utilization, size_t capacity, |
| const std::string& original_image_file_name, bool concurrent_gc, |
| size_t num_gc_threads, bool low_memory_mode); |
| |
| ~Heap(); |
| |
| // Allocates and initializes storage for an object instance. |
| mirror::Object* AllocObject(Thread* self, mirror::Class* klass, size_t num_bytes) |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); |
| |
| void RegisterNativeAllocation(int bytes) |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); |
| void RegisterNativeFree(int bytes) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); |
| |
| // The given reference is believed to be to an object in the Java heap, check the soundness of it. |
| void VerifyObjectImpl(const mirror::Object* o); |
| void VerifyObject(const mirror::Object* o) { |
| if (o != NULL && this != NULL && verify_object_mode_ > kNoHeapVerification) { |
| VerifyObjectImpl(o); |
| } |
| } |
| |
| // Check sanity of all live references. |
| void VerifyHeap() LOCKS_EXCLUDED(Locks::heap_bitmap_lock_); |
| bool VerifyHeapReferences() |
| EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_, Locks::mutator_lock_); |
| bool VerifyMissingCardMarks() |
| EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_) |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); |
| |
| // A weaker test than IsLiveObject or VerifyObject that doesn't require the heap lock, |
| // and doesn't abort on error, allowing the caller to report more |
| // meaningful diagnostics. |
| bool IsHeapAddress(const mirror::Object* obj); |
| |
| // Returns true if 'obj' is a live heap object, false otherwise (including for invalid addresses). |
| // Requires the heap lock to be held. |
| bool IsLiveObjectLocked(const mirror::Object* obj) |
| SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_); |
| |
| // Initiates an explicit garbage collection. |
| void CollectGarbage(bool clear_soft_references) LOCKS_EXCLUDED(Locks::mutator_lock_); |
| |
| // Does a concurrent GC, should only be called by the GC daemon thread |
| // through runtime. |
| void ConcurrentGC(Thread* self) LOCKS_EXCLUDED(Locks::runtime_shutdown_lock_); |
| |
| // Implements VMDebug.countInstancesOfClass and JDWP VM_InstanceCount. |
| // The boolean decides whether to use IsAssignableFrom or == when comparing classes. |
| void CountInstances(const std::vector<mirror::Class*>& classes, bool use_is_assignable_from, |
| uint64_t* counts) |
| LOCKS_EXCLUDED(Locks::heap_bitmap_lock_) |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); |
| // Implements JDWP RT_Instances. |
| void GetInstances(mirror::Class* c, int32_t max_count, std::vector<mirror::Object*>& instances) |
| LOCKS_EXCLUDED(Locks::heap_bitmap_lock_) |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); |
| // Implements JDWP OR_ReferringObjects. |
| void GetReferringObjects(mirror::Object* o, int32_t max_count, std::vector<mirror::Object*>& referring_objects) |
| LOCKS_EXCLUDED(Locks::heap_bitmap_lock_) |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); |
| |
| // Removes the growth limit on the alloc space so it may grow to its maximum capacity. Used to |
| // implement dalvik.system.VMRuntime.clearGrowthLimit. |
| void ClearGrowthLimit(); |
| |
| // Target ideal heap utilization ratio, implements |
| // dalvik.system.VMRuntime.getTargetHeapUtilization. |
| double GetTargetHeapUtilization() const { |
| return target_utilization_; |
| } |
| |
| // Data structure memory usage tracking. |
| void RegisterGCAllocation(size_t bytes); |
| void RegisterGCDeAllocation(size_t bytes); |
| |
| // Set target ideal heap utilization ratio, implements |
| // dalvik.system.VMRuntime.setTargetHeapUtilization. |
| void SetTargetHeapUtilization(float target); |
| |
| // For the alloc space, sets the maximum number of bytes that the heap is allowed to allocate |
| // from the system. Doesn't allow the space to exceed its growth limit. |
| void SetIdealFootprint(size_t max_allowed_footprint); |
| |
| // Blocks the caller until the garbage collector becomes idle and returns |
| // true if we waited for the GC to complete. |
| collector::GcType WaitForConcurrentGcToComplete(Thread* self) LOCKS_EXCLUDED(gc_complete_lock_); |
| |
| const std::vector<space::ContinuousSpace*>& GetContinuousSpaces() const { |
| return continuous_spaces_; |
| } |
| |
| const std::vector<space::DiscontinuousSpace*>& GetDiscontinuousSpaces() const { |
| return discontinuous_spaces_; |
| } |
| |
| void SetReferenceOffsets(MemberOffset reference_referent_offset, |
| MemberOffset reference_queue_offset, |
| MemberOffset reference_queueNext_offset, |
| MemberOffset reference_pendingNext_offset, |
| MemberOffset finalizer_reference_zombie_offset); |
| |
| mirror::Object* GetReferenceReferent(mirror::Object* reference); |
| void ClearReferenceReferent(mirror::Object* reference) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); |
| |
| // Returns true if the reference object has not yet been enqueued. |
| bool IsEnqueuable(const mirror::Object* ref); |
| void EnqueueReference(mirror::Object* ref, mirror::Object** list) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); |
| void EnqueuePendingReference(mirror::Object* ref, mirror::Object** list) |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); |
| mirror::Object* DequeuePendingReference(mirror::Object** list) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); |
| |
| MemberOffset GetReferencePendingNextOffset() { |
| DCHECK_NE(reference_pendingNext_offset_.Uint32Value(), 0U); |
| return reference_pendingNext_offset_; |
| } |
| |
| MemberOffset GetFinalizerReferenceZombieOffset() { |
| DCHECK_NE(finalizer_reference_zombie_offset_.Uint32Value(), 0U); |
| return finalizer_reference_zombie_offset_; |
| } |
| |
| // Enable verification of object references when the runtime is sufficiently initialized. |
| void EnableObjectValidation() { |
| verify_object_mode_ = kDesiredHeapVerification; |
| if (verify_object_mode_ > kNoHeapVerification) { |
| VerifyHeap(); |
| } |
| } |
| |
| // Disable object reference verification for image writing. |
| void DisableObjectValidation() { |
| verify_object_mode_ = kHeapVerificationNotPermitted; |
| } |
| |
| // Other checks may be performed if we know the heap should be in a sane state. |
| bool IsObjectValidationEnabled() const { |
| return kDesiredHeapVerification > kNoHeapVerification && |
| verify_object_mode_ > kHeapVerificationNotPermitted; |
| } |
| |
| // Returns true if low memory mode is enabled. |
| bool IsLowMemoryMode() const { |
| return low_memory_mode_; |
| } |
| |
| void RecordFree(size_t freed_objects, size_t freed_bytes); |
| |
| // Must be called if a field of an Object in the heap changes, and before any GC safe-point. |
| // The call is not needed if NULL is stored in the field. |
| void WriteBarrierField(const mirror::Object* dst, MemberOffset /*offset*/, const mirror::Object* /*new_value*/) { |
| card_table_->MarkCard(dst); |
| } |
| |
| // Write barrier for array operations that update many field positions |
| void WriteBarrierArray(const mirror::Object* dst, int /*start_offset*/, |
| size_t /*length TODO: element_count or byte_count?*/) { |
| card_table_->MarkCard(dst); |
| } |
| |
| accounting::CardTable* GetCardTable() const { |
| return card_table_.get(); |
| } |
| |
| void AddFinalizerReference(Thread* self, mirror::Object* object); |
| |
| // Returns the number of bytes currently allocated. |
| size_t GetBytesAllocated() const { |
| return num_bytes_allocated_; |
| } |
| |
| // Returns the number of objects currently allocated. |
| size_t GetObjectsAllocated() const; |
| |
| // Returns the total number of objects allocated since the heap was created. |
| size_t GetObjectsAllocatedEver() const; |
| |
| // Returns the total number of bytes allocated since the heap was created. |
| size_t GetBytesAllocatedEver() const; |
| |
| // Returns the total number of objects freed since the heap was created. |
| size_t GetObjectsFreedEver() const { |
| return total_objects_freed_ever_; |
| } |
| |
| // Returns the total number of bytes freed since the heap was created. |
| size_t GetBytesFreedEver() const { |
| return total_bytes_freed_ever_; |
| } |
| |
| // Implements java.lang.Runtime.maxMemory, returning the maximum amount of memory a program can |
| // consume. For a regular VM this would relate to the -Xmx option and would return -1 if no Xmx |
| // were specified. Android apps start with a growth limit (small heap size) which is |
| // cleared/extended for large apps. |
| int64_t GetMaxMemory() const { |
| return growth_limit_; |
| } |
| |
| // Implements java.lang.Runtime.totalMemory, returning the amount of memory consumed by an |
| // application. |
| int64_t GetTotalMemory() const; |
| |
| // Implements java.lang.Runtime.freeMemory. |
| int64_t GetFreeMemory() const { |
| return GetTotalMemory() - num_bytes_allocated_; |
| } |
| |
| // Get the space that corresponds to an object's address. Current implementation searches all |
| // spaces in turn. If fail_ok is false then failing to find a space will cause an abort. |
| // TODO: consider using faster data structure like binary tree. |
| space::ContinuousSpace* FindContinuousSpaceFromObject(const mirror::Object*, bool fail_ok) const; |
| space::DiscontinuousSpace* FindDiscontinuousSpaceFromObject(const mirror::Object*, |
| bool fail_ok) const; |
| space::Space* FindSpaceFromObject(const mirror::Object*, bool fail_ok) const; |
| |
| void DumpForSigQuit(std::ostream& os); |
| |
| size_t Trim(); |
| |
| accounting::HeapBitmap* GetLiveBitmap() SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_) { |
| return live_bitmap_.get(); |
| } |
| |
| accounting::HeapBitmap* GetMarkBitmap() SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_) { |
| return mark_bitmap_.get(); |
| } |
| |
| accounting::ObjectStack* GetLiveStack() SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_) { |
| return live_stack_.get(); |
| } |
| |
| void PreZygoteFork() LOCKS_EXCLUDED(Locks::heap_bitmap_lock_); |
| |
| // Mark and empty stack. |
| void FlushAllocStack() |
| EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_); |
| |
| // Mark all the objects in the allocation stack in the specified bitmap. |
| void MarkAllocStack(accounting::SpaceBitmap* bitmap, accounting::SpaceSetMap* large_objects, |
| accounting::ObjectStack* stack) |
| EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_); |
| |
| // Unmark all the objects in the allocation stack in the specified bitmap. |
| void UnMarkAllocStack(accounting::SpaceBitmap* bitmap, accounting::SpaceSetMap* large_objects, |
| accounting::ObjectStack* stack) |
| EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_); |
| |
| // Update and mark mod union table based on gc type. |
| void UpdateAndMarkModUnion(collector::MarkSweep* mark_sweep, base::TimingLogger& timings, |
| collector::GcType gc_type) |
| EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_); |
| |
| // Gets called when we get notified by ActivityThread that the process state has changed. |
| void ListenForProcessStateChange(); |
| |
| // DEPRECATED: Should remove in "near" future when support for multiple image spaces is added. |
| // Assumes there is only one image space. |
| space::ImageSpace* GetImageSpace() const; |
| |
| space::DlMallocSpace* GetAllocSpace() const { |
| return alloc_space_; |
| } |
| |
| space::LargeObjectSpace* GetLargeObjectsSpace() const { |
| return large_object_space_; |
| } |
| |
| void DumpSpaces(); |
| |
| // GC performance measuring |
| void DumpGcPerformanceInfo(std::ostream& os); |
| |
| // Thread pool. |
| void CreateThreadPool(); |
| void DeleteThreadPool(); |
| ThreadPool* GetThreadPool() { |
| return thread_pool_.get(); |
| } |
| |
| private: |
| // Allocates uninitialized storage. Passing in a null space tries to place the object in the |
| // large object space. |
| mirror::Object* Allocate(Thread* self, space::AllocSpace* space, size_t num_bytes) |
| LOCKS_EXCLUDED(Locks::thread_suspend_count_lock_) |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); |
| |
| // Try to allocate a number of bytes, this function never does any GCs. |
| mirror::Object* TryToAllocate(Thread* self, space::AllocSpace* space, size_t alloc_size, bool grow) |
| LOCKS_EXCLUDED(Locks::thread_suspend_count_lock_) |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); |
| |
| // Pushes a list of cleared references out to the managed heap. |
| void EnqueueClearedReferences(mirror::Object** cleared_references); |
| |
| void RequestHeapTrim() LOCKS_EXCLUDED(Locks::runtime_shutdown_lock_); |
| void RequestConcurrentGC(Thread* self) LOCKS_EXCLUDED(Locks::runtime_shutdown_lock_); |
| bool IsGCRequestPending() const; |
| |
| void RecordAllocation(size_t size, mirror::Object* object) |
| LOCKS_EXCLUDED(GlobalSynchronization::heap_bitmap_lock_) |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); |
| |
| // Sometimes CollectGarbageInternal decides to run a different Gc than you requested. Returns |
| // which type of Gc was actually ran. |
| collector::GcType CollectGarbageInternal(collector::GcType gc_plan, GcCause gc_cause, |
| bool clear_soft_references) |
| LOCKS_EXCLUDED(gc_complete_lock_, |
| Locks::heap_bitmap_lock_, |
| Locks::thread_suspend_count_lock_); |
| |
| void PreGcVerification(collector::GarbageCollector* gc); |
| void PreSweepingGcVerification(collector::GarbageCollector* gc) |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); |
| void PostGcVerification(collector::GarbageCollector* gc); |
| |
| // Update the watermark for the native allocated bytes based on the current number of native |
| // bytes allocated and the target utilization ratio. |
| void UpdateMaxNativeFootprint(); |
| |
| // Given the current contents of the alloc space, increase the allowed heap footprint to match |
| // the target utilization ratio. This should only be called immediately after a full garbage |
| // collection. |
| void GrowForUtilization(collector::GcType gc_type, uint64_t gc_duration); |
| |
| size_t GetPercentFree(); |
| |
| void AddContinuousSpace(space::ContinuousSpace* space) LOCKS_EXCLUDED(Locks::heap_bitmap_lock_); |
| void AddDiscontinuousSpace(space::DiscontinuousSpace* space) |
| LOCKS_EXCLUDED(Locks::heap_bitmap_lock_); |
| |
| // No thread saftey analysis since we call this everywhere and it is impossible to find a proper |
| // lock ordering for it. |
| void VerifyObjectBody(const mirror::Object *obj) NO_THREAD_SAFETY_ANALYSIS; |
| |
| static void VerificationCallback(mirror::Object* obj, void* arg) |
| SHARED_LOCKS_REQUIRED(GlobalSychronization::heap_bitmap_lock_); |
| |
| // Swap the allocation stack with the live stack. |
| void SwapStacks(); |
| |
| // Clear cards and update the mod union table. |
| void ProcessCards(base::TimingLogger& timings); |
| |
| // All-known continuous spaces, where objects lie within fixed bounds. |
| std::vector<space::ContinuousSpace*> continuous_spaces_; |
| |
| // All-known discontinuous spaces, where objects may be placed throughout virtual memory. |
| std::vector<space::DiscontinuousSpace*> discontinuous_spaces_; |
| |
| // The allocation space we are currently allocating into. |
| space::DlMallocSpace* alloc_space_; |
| |
| // The large object space we are currently allocating into. |
| space::LargeObjectSpace* large_object_space_; |
| |
| // The card table, dirtied by the write barrier. |
| UniquePtr<accounting::CardTable> card_table_; |
| |
| // The mod-union table remembers all of the references from the image space to the alloc / |
| // zygote spaces to allow the card table to be cleared. |
| UniquePtr<accounting::ModUnionTable> image_mod_union_table_; |
| |
| // This table holds all of the references from the zygote space to the alloc space. |
| UniquePtr<accounting::ModUnionTable> zygote_mod_union_table_; |
| |
| // What kind of concurrency behavior is the runtime after? True for concurrent mark sweep GC, |
| // false for stop-the-world mark sweep. |
| const bool concurrent_gc_; |
| |
| // How many GC threads we may use for garbage collection. |
| const bool num_gc_threads_; |
| |
| // Boolean for if we are in low memory mode. |
| const bool low_memory_mode_; |
| |
| // If we have a zygote space. |
| bool have_zygote_space_; |
| |
| // Guards access to the state of GC, associated conditional variable is used to signal when a GC |
| // completes. |
| Mutex* gc_complete_lock_ DEFAULT_MUTEX_ACQUIRED_AFTER; |
| UniquePtr<ConditionVariable> gc_complete_cond_ GUARDED_BY(gc_complete_lock_); |
| |
| // Mutex held when adding references to reference queues. |
| // TODO: move to a UniquePtr, currently annotalysis is confused that UniquePtr isn't lockable. |
| Mutex* reference_queue_lock_ DEFAULT_MUTEX_ACQUIRED_AFTER; |
| |
| // True while the garbage collector is running. |
| volatile bool is_gc_running_ GUARDED_BY(gc_complete_lock_); |
| |
| // Last Gc type we ran. Used by WaitForConcurrentGc to know which Gc was waited on. |
| volatile collector::GcType last_gc_type_ GUARDED_BY(gc_complete_lock_); |
| collector::GcType next_gc_type_; |
| |
| // Maximum size that the heap can reach. |
| const size_t capacity_; |
| // The size the heap is limited to. This is initially smaller than capacity, but for largeHeap |
| // programs it is "cleared" making it the same as capacity. |
| size_t growth_limit_; |
| // When the number of bytes allocated exceeds the footprint TryAllocate returns NULL indicating |
| // a GC should be triggered. |
| size_t max_allowed_footprint_; |
| // The watermark at which a concurrent GC is requested by registerNativeAllocation. |
| size_t native_footprint_gc_watermark_; |
| // The watermark at which a GC is performed inside of registerNativeAllocation. |
| size_t native_footprint_limit_; |
| |
| // Activity manager members. |
| jclass activity_thread_class_; |
| jclass application_thread_class_; |
| jobject activity_thread_; |
| jobject application_thread_; |
| jfieldID last_process_state_id_; |
| |
| // Process states which care about pause times. |
| std::set<int> process_state_cares_about_pause_time_; |
| |
| // Whether or not we currently care about pause times. |
| bool care_about_pause_times_; |
| |
| // When num_bytes_allocated_ exceeds this amount then a concurrent GC should be requested so that |
| // it completes ahead of an allocation failing. |
| size_t concurrent_start_bytes_; |
| |
| // Since the heap was created, how many bytes have been freed. |
| size_t total_bytes_freed_ever_; |
| |
| // Since the heap was created, how many objects have been freed. |
| size_t total_objects_freed_ever_; |
| |
| // Primitive objects larger than this size are put in the large object space. |
| const size_t large_object_threshold_; |
| |
| // Number of bytes allocated. Adjusted after each allocation and free. |
| AtomicInteger num_bytes_allocated_; |
| |
| // Bytes which are allocated and managed by native code but still need to be accounted for. |
| AtomicInteger native_bytes_allocated_; |
| |
| // Data structure GC overhead. |
| AtomicInteger gc_memory_overhead_; |
| |
| // Heap verification flags. |
| const bool verify_missing_card_marks_; |
| const bool verify_system_weaks_; |
| const bool verify_pre_gc_heap_; |
| const bool verify_post_gc_heap_; |
| const bool verify_mod_union_table_; |
| |
| // Parallel GC data structures. |
| UniquePtr<ThreadPool> thread_pool_; |
| |
| // Sticky mark bits GC has some overhead, so if we have less a few megabytes of AllocSpace then |
| // it's probably better to just do a partial GC. |
| const size_t min_alloc_space_size_for_sticky_gc_; |
| |
| // Minimum remaining size for sticky GC. Since sticky GC doesn't free up as much memory as a |
| // normal GC, it is important to not use it when we are almost out of memory. |
| const size_t min_remaining_space_for_sticky_gc_; |
| |
| // The last time a heap trim occurred. |
| uint64_t last_trim_time_ms_; |
| |
| // The nanosecond time at which the last GC ended. |
| uint64_t last_gc_time_ns_; |
| |
| // How many bytes were allocated at the end of the last GC. |
| uint64_t last_gc_size_; |
| |
| // Estimated allocation rate (bytes / second). Computed between the time of the last GC cycle |
| // and the start of the current one. |
| uint64_t allocation_rate_; |
| |
| // For a GC cycle, a bitmap that is set corresponding to the |
| UniquePtr<accounting::HeapBitmap> live_bitmap_ GUARDED_BY(Locks::heap_bitmap_lock_); |
| UniquePtr<accounting::HeapBitmap> mark_bitmap_ GUARDED_BY(Locks::heap_bitmap_lock_); |
| |
| // Mark stack that we reuse to avoid re-allocating the mark stack. |
| UniquePtr<accounting::ObjectStack> mark_stack_; |
| |
| // Allocation stack, new allocations go here so that we can do sticky mark bits. This enables us |
| // to use the live bitmap as the old mark bitmap. |
| const size_t max_allocation_stack_size_; |
| bool is_allocation_stack_sorted_; |
| UniquePtr<accounting::ObjectStack> allocation_stack_; |
| |
| // Second allocation stack so that we can process allocation with the heap unlocked. |
| UniquePtr<accounting::ObjectStack> live_stack_; |
| |
| // offset of java.lang.ref.Reference.referent |
| MemberOffset reference_referent_offset_; |
| |
| // offset of java.lang.ref.Reference.queue |
| MemberOffset reference_queue_offset_; |
| |
| // offset of java.lang.ref.Reference.queueNext |
| MemberOffset reference_queueNext_offset_; |
| |
| // offset of java.lang.ref.Reference.pendingNext |
| MemberOffset reference_pendingNext_offset_; |
| |
| // offset of java.lang.ref.FinalizerReference.zombie |
| MemberOffset finalizer_reference_zombie_offset_; |
| |
| // Minimum free guarantees that you always have at least min_free_ free bytes after growing for |
| // utilization, regardless of target utilization ratio. |
| size_t min_free_; |
| |
| // The ideal maximum free size, when we grow the heap for utilization. |
| size_t max_free_; |
| |
| // Target ideal heap utilization ratio |
| double target_utilization_; |
| |
| // Total time which mutators are paused or waiting for GC to complete. |
| uint64_t total_wait_time_; |
| |
| // Total number of objects allocated in microseconds. |
| const bool measure_allocation_time_; |
| AtomicInteger total_allocation_time_; |
| |
| // The current state of heap verification, may be enabled or disabled. |
| HeapVerificationMode verify_object_mode_; |
| |
| std::vector<collector::MarkSweep*> mark_sweep_collectors_; |
| |
| friend class collector::MarkSweep; |
| friend class VerifyReferenceCardVisitor; |
| friend class VerifyReferenceVisitor; |
| friend class VerifyObjectVisitor; |
| friend class ScopedHeapLock; |
| friend class space::SpaceTest; |
| |
| DISALLOW_IMPLICIT_CONSTRUCTORS(Heap); |
| }; |
| |
| } // namespace gc |
| } // namespace art |
| |
| #endif // ART_RUNTIME_GC_HEAP_H_ |