Ubuntu 18.04 配置Android9编译环境（一）

一、修改镜像源

sudo gedit /etc/apt/sources.list

修改替换内容如下 推荐使用中科大服务，速度较快。

deb https://mirrors.ustc.edu.cn/ubuntu/ bionic main restricted universe multiverse
deb-src https://mirrors.ustc.edu.cn/ubuntu/ bionic main restricted universe multiverse
deb https://mirrors.ustc.edu.cn/ubuntu/ bionic-updates main restricted universe multiverse
deb-src https://mirrors.ustc.edu.cn/ubuntu/ bionic-updates main restricted universe multiverse
deb https://mirrors.ustc.edu.cn/ubuntu/ bionic-backports main restricted universe multiverse
deb-src https://mirrors.ustc.edu.cn/ubuntu/ bionic-backports main restricted universe multiverse
deb https://mirrors.ustc.edu.cn/ubuntu/ bionic-security main restricted universe multiverse
deb-src https://mirrors.ustc.edu.cn/ubuntu/ bionic-security main restricted universe multiverse
deb https://mirrors.ustc.edu.cn/ubuntu/ bionic-proposed main restricted universe multiverse
deb-src https://mirrors.ustc.edu.cn/ubuntu/ bionic-proposed main restricted universe multiverse

使修改生效

 sudo apt-get update

二、配置openjdk8

1.安装jdk8

sudo apt-get install openjdk-8-jdk
sudo apt-get install openjdk-8-jre

2.安装编译Android源码依赖

sudo apt-get install libswitch-perl

sudo apt-get install libx11-dev:i386 libreadline6-dev:i386 libgl1-mesa-dev g++-multilib
sudo apt-get install -y git flex bison gperf build-essential libncurses5-dev:i386
sudo apt-get install tofrodos python-markdown libxml2-utils xsltproc zlib1g-dev:i386
sudo apt-get install dpkg-dev libsdl1.2-dev libesd0-dev
sudo apt-get install git-core gnupg flex bison gperf build-essential  
sudo apt-get install zip curl zlib1g-dev gcc-multilib g++-multilib
sudo apt-get install libc6-dev-i386
sudo apt-get install lib32ncurses5-dev x11proto-core-dev libx11-dev
sudo apt-get install libgl1-mesa-dev libxml2-utils xsltproc unzip m4
sudo apt-get install lib32z-dev ccache

#错误1 gcc-11不支持 需要切换会 gcc-9

/usr/bin/ld: scripts/dtc/dtc-parser.tab.o:(.bss+0x10): multiple definition of `yylloc'; scripts/dtc/dtc-lexer.lex.o:(.bss+0x0): first defined here
collect2: error: ld returned 1 exit status

三、修改cpu为高性能模式

安装 cpufrequtils:

    sudo apt-get install cpufrequtils

查看当前cpu的状态：

   cpufreq-info

把cpu调整到性能模式：

   sudo cpufreq-set -g performance

查看当前电脑CPU工作模式

cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor

如果没有启用高性能模式一般为：powersave

多核心的需要将所有的核全部调整到性能模式需要ROOT权限
echo "performance" |  tee /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor