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Optimizing the Cocos2D-X library A DS-5 Streamline case study

彭晓波/Bob Peng

Technical Marketing Manager,

Strategic Software Alliances

November 2013

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Agenda

Streamline Overview

Getting start with streamline

Cocos2d-x case study

* Event-based sampling is available on kernels 3.0 or later

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ARM DS-5TM Key Components

DS-5 IDE

• Powerful editor based on industry standard Eclipse CDT

• Hundreds of compatible plugins

Streamline Analyzer

• CPU, GPU, interconnect performance and power analysis

• Time- and event-based profiling

DS-5 Debugger

• Device bring-up and s/w development on single and multicore

• OS aware debug, on silicon, virtual platform and emulator

Compilation Tools

• ARM Compiler 5 – Bare-metal C/C++ and NEON vectorization

• Integrated Linaro GCC for ARM Linux

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Streamline Analyzer

Advantages

System-wide visibility into CPUs,

GPUs, interconnect, power

consumption and Linux/Android OS

resources

C/C++ source code level profiling

based on time or PMU events

Streaming data collection allowing

analysis as long as hours

Extensible data sources and

customizable data visualization

Trace hardware not required

Debug and optimize system performance and power

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Visualization of system performance, software profile and thread switching over time

Hierarchical profile table, aggregating samples per process, thread, and function call chain

Flat software profile table, listing shared libraries and function hotspots

Source and instruction level profile. Colour coded source code lines matching samples.

Dynamically created map of the functions in your application and their relationship

Dynamic analysis of the stack usage by your application

Analysis Overview

Chronologic list of text and graphic annotations sent to gator

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Timeline view: The Big Picture

Select from 40+ CPU counters,

OS level and custom metrics

Accumulate counters, measure time

and find instant hotspots

Select one or more processes to

visualize their instant load on CPU

Combined task switch trace and

sampled profile for all threads

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Performance Charts

CPU aware PMU registers 40+ core-level metrics to choose from

Mali graphics 300+ hardware and software counters

OS level statistics e.g. DVFS, interrupts, networking

Custom counters Easily add custom system counters

Event-based sampling Match PMU events to threads/source

code

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GPU Graphics Analysis

CPU, and GPU fragment and

vertex processing activity

Frame buffer filmstrip Hardware and Software counters

Visualize

application activity per processor

or processor activity per application

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Per core, per process activity

SMP Analysis

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big.LITTLETM Analysis

Inspect tasks moving between clusters

Cycle between aggregate, per cluster and per core

Consistent colouring between threads and counter charts

X-ray view

Counters

Disclosure control

Cycle between combined values (right arrow),

cluster values (as shown), per core (down arrow)

Core / cluster colour key

X-ray mode augmented with intermediate cluster mode

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Drilldown Software Profiling

Quickly identify instant hotspots

Filter timeline data to generate

focused software profile reports

Click on the function name

to go to source code level profile

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Call Graph view maps relationships between functions Easy to navigate dynamic function-level map

Dynamic Call Graph Analysis

Functions are colour coded

according to CPU time or events

Easily navigate along call paths and

identify caller/callee relationships

Function mapping can include

system and uncalled functions

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Power Measurement Interfaces

V

Visual Analysis

Automated Tests Str

eam

line

ARM Energy Probe

NI DAQ USB-62xx

• 3-channel

• System-level analysis

• Easy to deploy

• Affordable

Good for trend spotting and

application optimization

• 40+ analog inputs

• Subcomponent sensitivity

• High fidelity

• Higher cost

Good for OS power management

tuning and benchmarking

Da

ta A

cq

uis

itio

n

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Streamline Community vs. Basic/Pro

Which is the right

Streamline for you?

BSP / Distribution

Makers

OEMs / ODMs

Application developers

Ba

sic

/Pro

Ed

itio

ns

CE

Community Basic/Pro

Typical Use Case Simple application

profiling System-wide, SMP

analysis

Program Images 1 Limited to host

memory

Timeline View

* Performance Charts

* Process Bars

* Mali GPU Analysis

* Quick Profile Summary

* Core Affinity Mode

* Energy Probe data capture

* Time Filtering

* Annotation

Call Paths View

Functions View

Code View

Call Graph

Stack View

Log View

Command Line

Event Based Sampling

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Agenda

Streamline Overview

Getting start with streamline

Cocos2d-x case study

* Event-based sampling is available on kernels 3.0 or later

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Target Device Setup

IP-based connection to target No ICE/trace units required

Open source kernel module and daemon

Support for Linux kernel 2.6.32+

Kernel configuration PROFILING + PERF_EVENTS

FTRACE +

ENABLE_DEFAULT_TRACERS

HIGH_RES_TIMERS +

HW_PERF_EVENTS

LOCAL_TIMERS, if SMP

Reference blog: • 设置Android手机以使用ARM

Streamline进行性能分析一

User Space

ARM Processor

OpenGL® ES

Applications & Middleware

Linux Kernel

Mali Drivers

gator Daemon

gator Driver

TCP/IP

Targ

et D

evic

e

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Some Streamline-enabled Targets…

Pipo Smart-S1 Pro

Rikomagic MK802 II

Hardkernel Odroid

BlueTechnix SoM

Arndale board

HDMI Dongle (Cortex-A8 + Mali-

400) • Purchase link:

http://www.aliexpress.com/store/product/

New-arrival-Rikomagic-MK802-II-Mini-

Android-4-0-PC-Android-TV-Box-A10-

Cortex-A8/810525_651058884.html

• Tutorial book under \ARM-DS-5

• Blog : 如何利用全志安卓4.0 HDMI Dongle

进行ARM DS-5 Streamline性能分析

White-box Tablet (Dual-core Cortex® -A9

+ Quad-core Mali-400) • Purchase link:

http://detail.tmall.com/item.htm?id=22414055

832&

• Gator start automatically when power up

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Streamline data view Show

help Delete

View Style

Change

Streamline

Capture Data

Streamline

Analysis

Report

Start

Capture

Counter

Configuration

Capture

Options

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Setting Capture Options

Target address

“Localhost “

Or

“127.0.0.1”

Sample Rate:

Normal=1kHz, Low=100Hz, and None

Buffer Mode:

Large 16MB; Medium 4MB; Small 1MB

Capture Duration:

Format: Minute:Second (1:05)

Not filled meaning stop manually

Call Stack Unwining:

Streamline records call stacks or Not

Process Debug Information:

Streamline processes dwarf debug information and

line numbers or Not ?

High Resolution Timeline:

Streamline processes more data, enabling you to

zoom in three more levels in the Timeline view

Add elf image Add elf image

from workspace

Save caputre option

Or

Import from saved one

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Configure counters

Available Events List:

CPU events

Linux events

Mali GPU evens -VP/FP

Energy probe events

Events to be Collected:

Each event listed here is available

for display in the Timeline view

Delete

Import

Export

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Start Capture

Capturing… Stop and

generate analysis report

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Agenda

Streamline Overview

Getting start with streamline

Cocos2d-x case study

* Event-based sampling is available on kernels 3.0 or later

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Performance Bounds

CPU GPU

External

Memory

CPU Cache

BANDWIDTH Bound

Limited bandwidth

Frame buffer

GPU Cache

Bound

Bound

• Vertex

• Fragment

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CPU Optimization

Draw Calls --- As low as Possible

OpenCL

Offload some of the work to the GPU

Mali-T604 Support OpenCL Full profile

Neon optimization

Neon in opensource

projectNe10.org

Math – Vector/Matrix

DSP -- FFT/IFFT/FIR/IIR

Imgproc – Image resize/rotate

ARM v8(64bit)

OpenCL

Physics engine

Your input …

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NEONTM in Open Source Today Google WebM – 11,000 lines NEON assembler!

Bluez – official Linux Bluetooth protocol stack

Pixman (part of cairo 2D graphics library)

ffmpeg (libav) – libavcodec

LGPL media player used in many Linux distros and products

Extensive NEON optimizations

x264 – Google Summer Of Code 2009

GPL H.264 encoder – e.g. for video conferencing

Android – NEON optimizations

Skia library, S32A_D565_Opaque 5x faster using NEON

Available in Google Skia tree from 03-Aug-2009

LLVM – code generation backend used by Android RenderScript

Eigen2 – C++ vector math / linear algebra template library

TheorARM – libtheora NEON version (optimized by Google)

libjpeg / libjpeg-turbo – optimized JPEG decode

libpng – optimized PNG decode

FFTW – NEON enabled FFT library

Liboil / liborc – runtime compiler for SIMD processing

webkit – used by Chrome Browser

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Vertex Optimization

Using VBO (vertex buffer object)

Cache vertex data in GPU memory, no need copy from CPU every frame

Using culling

backface culling

view frustum culling

occlusion culling

Using LOD (Levels of Detail)

Remove unnecessary vertices

It’s Mobile, not PC!

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Fragment Optimization

Reducing Overdraw

Front to Back - Yes

Back to front - No

Limiting the amount of transparency in the scene

Using ETC texture

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Bandwidth Optimization

Bandwidth is a scarce resource

A typical embedded device can handle ≈ 5.0 Gigabytes a second of

bandwidth

A typical desktop GPU can do in excess of 100 Gigabytes a second

Use texture compression

The main popular format is ETC Texture Compression

This can help reduce your 32 bits per pixel texture into

a 4 bits per pixel texture

Mali Texture Compression Tool

use 16 bit textures instead of 32

You won’t often notice the difference

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Cocos2d-x Project : Introduction

What’s Cocos2d-x ? Cross-platform, open source (MIT) 2D game engine

Used by 25% of worldwide mobile games

1.5+ billion cocos2d-based games downloads

Supports C++, Javascript and Lua

Profiling SW • Cocos2d-x Benchmark

• Game rebuild with symbol file (FishJoy, 忘仙）

Profiling HW Entry-level smartphone

Cotex A5 + Mali300

Android version: ICS

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Profiling story 1: NodeChildren iterate test

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Profiling story 2 : Performance test Sprite A

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Profiling story 3: Fishjoy2(Start Game)

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Profiling Story 4: FishJoy2(Quick click to play the game)

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Reference

Blog post

@cocos2d-x.org http://www.cocos2d-x.org/news/137

Current status

Chinese key mobile internet companies start using Streamline itself now

Alibaba inc.

Tencent inc

Ucweb inc

Cocos2d-x

Sohu Game