Approximate the GPU frame time by computing a difference between the smallest GPUStartTime and largest GPUEndTime for all command buffers submitted in a frame workload. More...

#include <gpu_tracer_mtl.h>

Inheritance diagram for impeller::GPUTracerMTL:

Public Member Functions
	GPUTracerMTL ()=default

	~GPUTracerMTL ()=default

void	MarkFrameEnd ()
	Record that the current frame has ended. Any additional cmd buffers will be attributed to the "next" frame. More...

void	RecordCmdBuffer (id< MTLCommandBuffer > buffer)
	Record the current cmd buffer GPU execution timestamps into an aggregate frame workload metric. More...

Detailed Description

Approximate the GPU frame time by computing a difference between the smallest GPUStartTime and largest GPUEndTime for all command buffers submitted in a frame workload.

Definition at line 23 of file gpu_tracer_mtl.h.

Constructor & Destructor Documentation

◆ GPUTracerMTL()

impeller::GPUTracerMTL::GPUTracerMTL ( )

default

◆ ~GPUTracerMTL()

impeller::GPUTracerMTL::~GPUTracerMTL ( )

default

Member Function Documentation

◆ MarkFrameEnd()

void impeller::GPUTracerMTL::MarkFrameEnd ( )

Record that the current frame has ended. Any additional cmd buffers will be attributed to the "next" frame.

Definition at line 16 of file gpu_tracer_mtl.mm.

                                 {
   if (@available(ios 10.3, tvos 10.2, macos 10.15, macCatalyst 13.0, *)) {
     Lock lock(trace_state_mutex_);
     current_state_ = (current_state_ + 1) % 16;
   }
 }

◆ RecordCmdBuffer()

void impeller::GPUTracerMTL::RecordCmdBuffer ( id< MTLCommandBuffer > buffer )

Record the current cmd buffer GPU execution timestamps into an aggregate frame workload metric.

Definition at line 23 of file gpu_tracer_mtl.mm.

                                                               {
   if (@available(ios 10.3, tvos 10.2, macos 10.15, macCatalyst 13.0, *)) {
     Lock lock(trace_state_mutex_);
     auto current_state = current_state_;
     trace_states_[current_state].pending_buffers += 1;
  
     auto weak_self = weak_from_this();
     [buffer addCompletedHandler:^(id<MTLCommandBuffer> buffer) {
       auto self = weak_self.lock();
       if (!self) {
         return;
       }
       Lock lock(self->trace_state_mutex_);
       auto& state = self->trace_states_[current_state];
       state.pending_buffers--;
       state.smallest_timestamp = std::min(
           state.smallest_timestamp, static_cast<Scalar>(buffer.GPUStartTime));
       state.largest_timestamp = std::max(
           state.largest_timestamp, static_cast<Scalar>(buffer.GPUEndTime));
  
       if (state.pending_buffers == 0) {
         auto gpu_ms =
             (state.largest_timestamp - state.smallest_timestamp) * 1000;
         state.smallest_timestamp = std::numeric_limits<float>::max();
         state.largest_timestamp = 0;
         FML_TRACE_COUNTER("flutter", "GPUTracer",
                           reinterpret_cast<int64_t>(this),  // Trace Counter ID
                           "FrameTimeMS", gpu_ms);
       }
     }];
   }
 }

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

impeller/renderer/backend/metal/gpu_tracer_mtl.h
impeller/renderer/backend/metal/gpu_tracer_mtl.mm