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对于a,b是table对象的情况下,需要特别判断一下，返回false.

table.sort(allTab, function(a, b)
    if a == b then
        return false -- first sort may a == b, must return false
    end
end)

环境搭建

$ yum -y install gcc
$ yum -y install g++
$ yum install libXtst-devel libXt-devel libXrender-devel libXrandr-devel cups-devel fontconfig-devel alsa-lib-devel

编译

$ bash ./configure --with-extra-cxxflags="-Wno-error" \
--with-extra-cflags="-Wno-error" \
--enable-unlimited-crypto \
--with-native-debug-symbols=none \
--with-debug-level=release \
--with-target-bits=64 \
--with-boot-jdk=/home/jdks/dragonwell-11.0.17.13+8-GA
$ make images
$ ./build/linux-aarch64-normal-server-release/images/jdk/bin/java -version

生动好文mark: Linux网络内核参数优化秘籍

$ bin/jlink --module-path jmods --add-modules java.desktop --output jre

错误信息： client_loop: send disconnect: Broken pipe

以macOS的ssh客户端为例

$ cd /etc/ssh
$ sudo vim ssh_config

在ssh_config文件的最下方的Host *中新增

    ServerAliveInterval 30
    IPQoS=throughput

JDK源码

• jdk8u
• jdk11u
• jdk17u

JDK安装包(boot jdk)

从adoptium下载

安装boot jdk

修改PATH搜索顺序来访问自己的jdk，避免和系统已存在的jdk冲突。

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使用下面的命令进行查询

$ /usr/libexec/java_home -V

Lua源码未自带windows编译脚本, 自行编译过程如下

1. 启动Visual Studio 控制台环境，以2019为例，cmd中运行下面的脚本

   D:\Program Files (x86)\Microsoft Visual Studio\2019\Community\VC\Auxiliary\Build\vcvars64.bat

2. 在切换到lua-5.x.x/src目录下

3. 运行下面的bat脚本进行编译

   cl /MD /O2 /c /DLUA_BUILD_AS_DLL *.c
   ren lua.obj lua.o
   ren luac.obj luac.o
   link /DLL /IMPLIB:lua.lib /OUT:lua.dll *.obj
   link /OUT:lua.exe lua.o lua.lib
   lib /OUT:lua-static.lib *.obj
   link /OUT:luac.exe luac.o lua-static.lib

Spark 官方提供的二进制下载版本缺少对Hive的支持，需要自己下载源码进行编译，加入hive的支持。

解压并修改maven repo为国内地址源(有2处)。

$ tar zxvf spark-3.2.1.tgz
$ cd spark-3.2.1
$ vim pom.xml
<!--url>https://maven-central.storage-download.googleapis.com/maven2/</url-->
<url>https://maven.aliyun.com/repository/public</url>

编译

$ export MAVEN_OPTS="-Xss64m -Xmx2g -XX:ReservedCodeCacheSize=1g"
$ ./dev/make-distribution.sh --name hadoop-3.3.2-hive-3.1.3 --tgz -Pyarn -Dhadoop.version=3.3.2 -Phive -Phive-thriftserver -DskipTests

其中-Phive -Phive-thriftserver参数就是启用hive支持，MAVEN_OPTS参数必须的，否则编译过程中会提示java内存不足.

安装

$ sudo apt install mysql-server

查看默认账号密码

$ sudo cat /etc/mysql/debian.cnf
# Automatically generated for Debian scripts. DO NOT TOUCH!
[client]
host     = localhost
user     = debian-sys-maint
password = JRvfA0JiQGk5qhnz
socket   = /var/run/mysqld/mysqld.sock
[mysql_upgrade]
host     = localhost
user     = debian-sys-maint
password = JRvfA0JiQGk5qhnz
socket   = /var/run/mysqld/mysqld.sock

修改密码

$ mysql -udebian-sys-maint -pJRvfA0JiQGk5qhnz

mysql>USE mysql;

// mysql 5.7
mysql>UPDATE user SET plugin='mysql_native_password' WHERE User='root';
mysql>update mysql.user set authentication_string=password('xxx') where User='root' and Host='localhost';
// mysql 8.0
mysql>ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password BY 'xxx';

mysql>flush privileges;
mysql>exit;