RocketMQ的坑（一）–搭好环境跑起来

主要问题：

• VM内存不足
• 找不到主类
• linux下找不到java环境变量

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VM内存不足

• 问题：
  Error occurred during initialization of VM
  Could not reserve enough space for 2097152KB object heap
• 解决办法：
  修改bin下的runserver脚本，把set “JAVA_OPT=%JAVA_OPT% -server -Xms500m -Xmx500m -Xmn500m -XX:PermSize=128m -XX:MaxPermSize=320m”的Xms、Xmx、Xmn改小点。相关知识见jvm。
• 解决后：
  

找不到主类

• 解决办法
  更新maven版本 ，官方要求3.2.x，而我的mavne是3.1.1

linux下找不到java环境变量

• 问题描述

ERROR: Please set the JAVA_HOME variable in your environment, We need java(x64)! !!

• 解决办法:modify runserver.sh

vim runserver.sherror_exit (){    echo "ERROR: $1 !!"    exit 1}JAVA_HOME=/home/orca/java/jdk1.8.0_144#[ ! -e "$JAVA_HOME/bin/java" ] && JAVA_HOME=$HOME/jdk/java#[ ! -e "$JAVA_HOME/bin/java" ] && JAVA_HOME=/usr/java#[ ! -e "$JAVA_HOME/bin/java" ] && error_exit "Please set the JAVA_HOME variable in your environment, We need java(x64)!"$sudo export JAVA_HOME$sudo export JAVA="$JAVA_HOME/bin/java"$sudo export BASE_DIR=$(dirname $0)/..$sudo export CLASSPATH=.:${BASE_DIR}/conf:${CLASSPATH}#===========================================================================================# JVM Configuration#===========================================================================================JAVA_OPT="${JAVA_OPT} -server -Xms4g -Xmx4g -Xmn2g -XX:PermSize=128m -XX:MaxPermSize=320m"JAVA_OPT="${JAVA_OPT} -XX:+UseConcMarkSweepGC -XX:+UseCMSCompactAtFullCollection -XX:CMSInitiatingOccupancyFraction=70 -XX:+CMSParallelRemarkEnabled -XX:SoftRefLRUPolicyMSPerMB=0 -XX:+CMSClassUnloadingEnabled -XX:SurvivorRatio=8 -XX:+DisableExplicitGC -XX:-UseParNewGC"JAVA_OPT="${JAVA_OPT} -verbose:gc -Xloggc:/dev/shm/rmq_srv_gc.log -XX:+PrintGCDetails"JAVA_OPT="${JAVA_OPT} -XX:-OmitStackTraceInFastThrow"JAVA_OPT="${JAVA_OPT}  -XX:-UseLargePages"JAVA_OPT="${JAVA_OPT} -Djava.ext.dirs=${BASE_DIR}/lib"#JAVA_OPT="${JAVA_OPT} -Xdebug -Xrunjdwp:transport=dt_socket,address=9555,server=y,suspend=n"JAVA_OPT="${JAVA_OPT} ${JAVA_OPT_EXT}"JAVA_OPT="${JAVA_OPT} -cp ${CLASSPATH}"$sudo java ${JAVA_OPT} $@