HeapProfiler Class Reference

#include <v8-profiler.h>

Data Structures
class	ObjectNameResolver

Public Types
typedef RetainedObjectInfo *(*	WrapperInfoCallback )(uint16_t class_id, Handle< Value > wrapper)

Public Member Functions
int	GetSnapshotCount ()
const HeapSnapshot *	GetHeapSnapshot (int index)
SnapshotObjectId	GetObjectId (Handle< Value > value)
Handle< Value >	FindObjectById (SnapshotObjectId id)
void	ClearObjectIds ()
const HeapSnapshot *	TakeHeapSnapshot (Handle< String > title, ActivityControl *control=NULL, ObjectNameResolver *global_object_name_resolver=NULL)
void	StartTrackingHeapObjects (bool track_allocations=false)
SnapshotObjectId	GetHeapStats (OutputStream *stream)
void	StopTrackingHeapObjects ()
void	DeleteAllHeapSnapshots ()
void	SetWrapperClassInfoProvider (uint16_t class_id, WrapperInfoCallback callback)
size_t	GetProfilerMemorySize ()
void	SetRetainedObjectInfo (UniqueId id, RetainedObjectInfo *info)

Static Public Attributes
static const SnapshotObjectId	kUnknownObjectId = 0
static const uint16_t	kPersistentHandleNoClassId = 0

Detailed Description

Interface for controlling heap profiling. Instance of the profiler can be retrieved using v8::Isolate::GetHeapProfiler.

Definition at line 401 of file v8-profiler.h.

Member Typedef Documentation

typedef RetainedObjectInfo*(* WrapperInfoCallback)(uint16_t class_id, Handle< Value > wrapper)

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.

Definition at line 410 of file v8-profiler.h.

Member Function Documentation

void ClearObjectIds

(

)

Clears internal map from SnapshotObjectId to heap object. The new objects will not be added into it unless a heap snapshot is taken or heap object tracking is kicked off.

Definition at line 7360 of file api.cc.

Referenced by TEST().

void DeleteAllHeapSnapshots

(

)

Deletes all snapshots taken. All previously returned pointers to snapshots and their contents become invalid after this call.

Definition at line 7391 of file api.cc.

Referenced by TEST().

Handle< Value > FindObjectById

(

SnapshotObjectId

id

)

Returns heap object with given SnapshotObjectId if the object is alive, otherwise empty handle is returned.

Definition at line 7352 of file api.cc.

References Handle< T >::is_null(), and Utils::ToLocal().

Referenced by TEST().

const HeapSnapshot * GetHeapSnapshot

(

int

index

)

Returns a snapshot by index.

Definition at line 7340 of file api.cc.

SnapshotObjectId GetHeapStats

(

OutputStream *

stream

)

Adds a new time interval entry to the aggregated statistics array. The time interval entry contains information on the current heap objects population size. The method also updates aggregated statistics and reports updates for all previous time intervals via the OutputStream object. Updates on each time interval are provided as a stream of the HeapStatsUpdate structure instances. The return value of the function is the last seen heap object Id.

StartTrackingHeapObjects must be called before the first call to this method.

Definition at line 7386 of file api.cc.

SnapshotObjectId GetObjectId

(

Handle< Value >

value

)

Returns SnapshotObjectId for a heap object referenced by |value| if it has been seen by the heap profiler, kUnknownObjectId otherwise.

Definition at line 7346 of file api.cc.

References Utils::OpenHandle().

Referenced by TEST().

size_t GetProfilerMemorySize

(

)

Returns memory used for profiler internal data and snapshots.

Definition at line 7403 of file api.cc.

int GetSnapshotCount

(

)

Returns the number of snapshots taken.

Definition at line 7335 of file api.cc.

Referenced by TEST().

void SetRetainedObjectInfo	(	UniqueId	id,
		RetainedObjectInfo *	info
	)

Sets a RetainedObjectInfo for an object group (see V8::SetObjectGroupId).

Definition at line 7409 of file api.cc.

void SetWrapperClassInfoProvider	(	uint16_t	class_id,
		WrapperInfoCallback	callback
	)

Binds a callback to embedder's class ID.

Definition at line 7396 of file api.cc.

Referenced by TEST().

void StartTrackingHeapObjects

(

bool

track_allocations = false

)

Starts tracking of heap objects population statistics. After calling this method, all heap objects relocations done by the garbage collector are being registered.

|track_allocations| parameter controls whether stack trace of each allocation in the heap will be recorded and reported as part of HeapSnapshot.

Definition at line 7375 of file api.cc.

Referenced by TEST().

void StopTrackingHeapObjects

(

)

Stops tracking of heap objects population statistics, cleans up all collected data. StartHeapObjectsTracking must be called again prior to calling PushHeapObjectsStats next time.

Definition at line 7381 of file api.cc.

Referenced by TEST().

const HeapSnapshot * TakeHeapSnapshot	(	Handle< String >	title,
		ActivityControl *	control = NULL,
		ObjectNameResolver *	global_object_name_resolver = NULL
	)

Takes a heap snapshot and returns it. Title may be an empty string.

Definition at line 7365 of file api.cc.

References Utils::OpenHandle().

Referenced by HasWeakGlobalHandle(), and TEST().

Field Documentation

const uint16_t kPersistentHandleNoClassId = 0

static

Default value of persistent handle class ID. Must not be used to define a class. Can be used to reset a class of a persistent handle.

Definition at line 514 of file v8-profiler.h.

Referenced by GlobalHandles::Node::Acquire(), HeapProfiler::DefineWrapperClass(), GlobalHandles::Node::has_wrapper_class_id(), and GlobalHandles::Node::Release().

const SnapshotObjectId kUnknownObjectId = 0

static

A constant for invalid SnapshotObjectId. GetSnapshotObjectId will return it in case heap profiler cannot find id for the object passed as parameter. HeapSnapshot::GetNodeById will always return NULL for such id.

Definition at line 442 of file v8-profiler.h.

Referenced by HeapProfiler::GetSnapshotObjectId(), and TEST().

---

The documentation for this class was generated from the following files:

• include/v8-profiler.h
• src/api.cc