Camera 冷启动Systrace 拆解

和你一起终身学习，这里是程序员Android

经典好文推荐，通过阅读本文，您将收获以下知识点:

一、Camx trace 调试开关设置
二、Camx 调试开关设置懒人脚本
三、Camera 冷启动阶段分解分析

一、Camx trace 调试开关设置

1.设置 camxoverridesettings trace开关

adb  root
    adb  remount
    adb  shell "rm -rf /vendor/etc/camera/camxoverridesettings.txt"
    adb  shell "touch  /vendor/etc/camera/camxoverridesettings.txt"
    adb  shell "echo traceGroupsEnable=0x10080 >> /vendor/etc/camera/camxoverridesettings.txt"
    adb  shell "echo traceErrorEnable=TRUE     >> /vendor/etc/camera/camxoverridesettings.txt"
    adb  shell "echo traceOutputEnable=0x10080 >> /vendor/etc/camera/camxoverridesettings.txt"
    adb reboot

2. 重启后设置开启camx trace 开关

因为 camxoverridesettings 只有重启之后可以生效，所以重启完成后需要开启trace 开关，既可以开始抓取Camera的 Systrace。

adb shell "echo 1 > d/tracing/events/camera/enable"

二、Camx 调试开关设置懒人脚本

下面脚本主要用来设置Camx debug trace 开关的，内容如下：

#bin/bash

# setting camxoverridesettings prop
funSetCamxoverridesettings(){

    adb  shell "echo traceGroupsEnable=0x10080 >> /vendor/etc/camera/camxoverridesettings.txt"
    adb  shell "echo traceErrorEnable=TRUE     >> /vendor/etc/camera/camxoverridesettings.txt"
    adb  shell "echo traceOutputEnable=0x10080 >> /vendor/etc/camera/camxoverridesettings.txt"
}

# setting CameraTrace prop
funEnableCameraTrace(){

    adb shell "echo 1 > d/tracing/events/camera/enable"
}

# cat setting result
funCatCameraProp(){
    echo "--------------------------------------------"
    echo "please check Camera trace prop is set sucess"
    echo "--------------------------------------------"
    echo "camxoverridesettings prop :*****************"
    adb shell cat /vendor/etc/camera/camxoverridesettings.txt
    echo "tracing prop :******************************"
    adb shell cat d/tracing/events/camera/enable
}

# it's only used in debug version
funRemountDevice(){
    adb root
    adb remount
    
    if [ $? -eq 0 ]; then

     echo "remount success"
     funSetCamxoverridesettings
     adb shell cat  /vendor/etc/camera/camxoverridesettings.txt

     for((i=0;$i<=10;i++))
         do
         sleep 1
         echo "waring !!! the phone will reboot after $i s"
         done

     adb reboot
    
    for((i=0;$i<=50;i++))
         do
         sleep 1
         echo "waiting phone is reboot after  $i s "
         done
         adb root
         adb remount
         funEnableCameraTrace
         funCatCameraProp
    else
    
     echo "remount failed,please remount the devices"
     
    fi
}


# main 
funRemountDevice
echo "input any num exit "
read num

查看Camera 相关进程

测试后查看下Camera 相关进程，有助于后续Systrace 有选择的分析查看。

C:\Users\ProgramAndroid>adb shell  ps | findstr camera
cameraserver   810     1 4396356 124740 0                   0 S android.hardware.camera.provider@2.4-service_64
cameraserver   807     1   37792   3240 0                   0 S vendor.oneplus.hardware.camera@1.0-service
cameraserver  1418     1   69628  11096 0                   0 S cameraserver
system        6519   683 5221532  33168 0                   0 S com.oneplus.camera.service
u0_a130       9163   683 6052676  46388 0                   0 S com.oneplus.camera.pictureprocessing
system       10641   683 5594508  84672 0                   0 S com.wingtech.cameraCalibration
u0_a138      12467   683 7046152 135544 0                   0 S com.oneplus.camera

三、Camera 冷启动阶段分解分析

1. 从 TouchUp 到 ActivityStart 耗时

从Touch UP 到 ActivityStart 阶段，系统创建App进程耗时：

• 1.PostFork 耗时需要排查 Zygote.java 代码

Zygote.java frameworks\base\core\java\com\android\internal\os

• 1. ZygoteInit 耗时需要排查ZygoteInit.java 代码

ZygoteInit.java frameworks\base\core\java\com\android\internal\os

• 3.ActivityThreadMain耗时需要排查ActivityThread.java代码

ActivityThread.java frameworks\base\core\java\android\app

• 1. bindApplication 耗时需要排查ActivityThread.java代码,同上

2. 从 ActivityStart 到 App 层 OpenCamera 耗时

1. App 开始执行 MainActivity 一系列 onCreate，onStart，onResume，openCamera等操作

2.Framework层 cameraserver 开始响应App getCameraCharacteristics 、connectDevice 等操作。

camera Server 在此期间的行为

• 1. activityStart 耗时需要排查 LaunchActivityItem.java 代码
     LaunchActivityItem.java frameworks\base\core\java\android\app\servertransaction
• 1. ResumeActivityItem耗时需要排查 ResumeActivityItem.java 代码
     ResumeActivityItem.java frameworks\base\core\java\android\app\servertransaction
• 1. Choreographer#doFrame 耗时需要排查 Choreographer.java 代码
     Choreographer.java frameworks\base\core\java\android\view

3.HAL 层 OpenCamera耗时

HAL 层开始响应 APP OpenCamera的操作，并返回 open状态 给APP。

Camera HAL OpenCamera 耗时

• 1. camera_module->open 耗时需要排查hal 层 CameraModule.cpp open 方法中的耗时

CameraModule.cpp hardware\interface\camera\common\1.0\default

4.APP 层 OpenCameraDone 到ConfigureStreams

5.HAL 层 ConfigureStreams 耗时

6. APP 层 ConfigureStreams Done 到 SetRepeatingRequests

7.SetRepeatingRequests 到 第一帧HAL3ProcessCaptureResult

8.HAL3ProcessCaptureResult 到第一帧Preview

9.Camera APP冷启动总耗时

至此，本篇已结束。转载网络的文章，小编觉得很优秀，欢迎点击阅读原文，支持原创作者，如有侵权，恳请联系小编删除，欢迎您的建议与指正。同时期待您的关注，感谢您的阅读，谢谢！

点个在看，为大佬点赞！