Module track_event 

Nested message and enum types in TrackEvent.

Modules

callstack

Nested message and enum types in Callstack.

legacy_event

Nested message and enum types in LegacyEvent.

Structs

Callstack

Inline callstack for TrackEvents when interning is not needed. This is a simplified version of the profiling Callstack/Frame messages, designed for cases where trace size is not critical or callstacks are unique.

LegacyEvent

Apart from {category, time, thread time, tid, pid}, other legacy trace event attributes are initially simply proxied for conversion to a JSON trace. We intend to gradually transition these attributes to similar native features in TrackEvent (e.g. async + flow events), or deprecate them without replacement where transition is unsuitable.

Enums

CallstackField

Callstack associated with this event. This captures the program stack at the time the event occurred, useful for understanding what code path led to the event.

CorrelationIdField

An opaque identifier to correlate this slice with other slices that are considered part of the same logical operation, even if they are not causally connected. Examples uses of a correlation id might be the number of frame going through various stages of rendering in a GPU, the id for an RPC request going through a distributed system, or the id of a network request going through various stages of processing by the kernel.

CounterValueField

A new value for a counter track. |track_uuid| should refer to a track with a CounterDescriptor, and |type| should be TYPE_COUNTER. For a more efficient encoding of counter values that are sampled at the beginning/end of a slice, see |extra_counter_values| and |extra_counter_track_uuids|. Counter values can optionally be encoded in as delta values (positive or negative) on each packet sequence (see CounterIncrementalBase).

NameField

Optional name of the event for its display in trace viewer. May be left unspecified for events with typed arguments.

SourceLocationField

This field is used only if the source location represents the function that executes during this event.

ThreadInstructionCount

Deprecated. Use |extra_counter_values| and |extra_counter_track_uuids| to encode thread instruction count instead.

ThreadTime

Deprecated. Use |extra_counter_values| and |extra_counter_track_uuids| to encode thread time instead.

Timestamp

Deprecated. Use the |timestamp| and |timestamp_clock_id| fields in TracePacket instead.

Type

Type of the TrackEvent (required if |phase| in LegacyEvent is not set).