运行环境：
- CentOS Linux release 7.8.2003 (Core) - openjdk 版本“11.0.8” 2020-07-14 LTS - rocketmq-all-4.7.1-bin-release
序言：
为了快速启动和运行，我将下载一个二进制版本。无需构建二进制工件。
问题描述：
由于RocketMQ启动脚本不支持java11，所以我根据网络搜索对启动文件进行了修改，修改文件runserver.sh、runbroker.sh、tools.sh大致相同主意。配置文件如下。
运行服务器.sh
# JAVA_OPT="${JAVA_OPT} -server -Xms4g -Xmx4g -Xmn2g -XX:MetaspaceSize=128m -XX:MaxMetaspaceSize=320m"
JAVA_OPT="${JAVA_OPT} -server -Xms500m -Xmx500m -Xmn250m -XX:MetaspaceSize=128m -XX:MaxMetaspaceSize=320m"
# JAVA_OPT="${JAVA_OPT} -XX:+UseConcMarkSweepGC -XX:+UseCMSCompactAtFullCollection -XX:CMSInitiatingOccupancyFraction=70 -XX:+CMSParallelRemarkEnabled -XX:SoftRefLRUPolicyMSPerMB=0 -XX:+CMSClassUnloadingEnabled -XX:SurvivorRatio=8 -XX:-UseParNewGC"
JAVA_OPT="${JAVA_OPT} -XX:CMSInitiatingOccupancyFraction=70 -XX:+CMSParallelRemarkEnabled -XX:SoftRefLRUPolicyMSPerMB=0 -XX:+CMSClassUnloadingEnabled -XX:SurvivorRatio=8"
# JAVA_OPT="${JAVA_OPT} -verbose:gc -Xloggc:${GC_LOG_DIR}/rmq_srv_gc_%p_%t.log -XX:+PrintGCDetails"
JAVA_OPT="${JAVA_OPT} -verbose:gc -Xlog:gc:${GC_LOG_DIR}/rmq_srv_gc_%p_%t.log"
# JAVA_OPT="${JAVA_OPT} -XX:+UseGCLogFileRotation -XX:NumberOfGCLogFiles=5 -XX:GCLogFileSize=30m"
JAVA_OPT="${JAVA_OPT} -XX:-OmitStackTraceInFastThrow"
JAVA_OPT="${JAVA_OPT} -XX:-UseLargePages"
# JAVA_OPT="${JAVA_OPT} -Djava.ext.dirs=${JAVA_HOME}/jre/lib/ext:${BASE_DIR}/lib:${JAVA_HOME}/lib/ext"
#JAVA_OPT="${JAVA_OPT} -Xdebug -Xrunjdwp:transport=dt_socket,address=9555,server=y,suspend=n"
运行经纪人.sh
# JAVA_OPT="${JAVA_OPT} -server -Xms8g -Xmx8g -Xmn4g"
JAVA_OPT="${JAVA_OPT} -server -Xms500m -Xmx500m -Xmn250m"
JAVA_OPT="${JAVA_OPT} -XX:+UseG1GC -XX:G1HeapRegionSize=16m -XX:G1ReservePercent=25 -XX:InitiatingHeapOccupancyPercent=30 -XX:SoftRefLRUPolicyMSPerMB=0"
# JAVA_OPT="${JAVA_OPT} -verbose:gc -Xloggc:${GC_LOG_DIR}/rmq_broker_gc_%p_%t.log -XX:+PrintGCDetails -XX:+PrintGCDateStamps -XX:+PrintGCApplicationStoppedTime -XX:+PrintAdaptiveSizePolicy"
JAVA_OPT="${JAVA_OPT} -verbose:gc -Xlogi:gc:${GC_LOG_DIR}/rmq_broker_gc_%p_%t.log"
# JAVA_OPT="${JAVA_OPT} -XX:+UseGCLogFileRotation -XX:NumberOfGCLogFiles=5 -XX:GCLogFileSize=30m"
JAVA_OPT="${JAVA_OPT} -XX:-OmitStackTraceInFastThrow"
JAVA_OPT="${JAVA_OPT} -XX:+AlwaysPreTouch"
JAVA_OPT="${JAVA_OPT} -XX:MaxDirectMemorySize=15g"
JAVA_OPT="${JAVA_OPT} -XX:-UseLargePages -XX:-UseBiasedLocking"
# JAVA_OPT="${JAVA_OPT} -Djava.ext.dirs=${JAVA_HOME}/jre/lib/ext:${BASE_DIR}/lib:${JAVA_HOME}/lib/ext"
#JAVA_OPT="${JAVA_OPT} -Xdebug -Xrunjdwp:transport=dt_socket,address=9555,server=y,suspend=n"
工具.sh
# JAVA_OPT="${JAVA_OPT} -server -Xms1g -Xmx1g -Xmn256m -XX:MetaspaceSize=128m -XX:MaxMetaspaceSize=128m"
JAVA_OPT="${JAVA_OPT} -server -Xms500m -Xmx500m -Xmn256m -XX:MetaspaceSize=128m -XX:MaxMetaspaceSize=128m"
# JAVA_OPT="${JAVA_OPT} -Djava.ext.dirs=${BASE_DIR}/lib:${JAVA_HOME}/jre/lib/ext:${JAVA_HOME}/lib/ext"
启动 RocketMQ NameServer
./mqnamesrv
[0.008s][info][gc] Using G1
错误: 找不到或无法加载主类 org.apache.rocketmq.namesrv.NamesrvStartup
原因: java.lang.ClassNotFoundException: org.apache.rocketmq.namesrv.NamesrvStartup
之后我尝试添加环境变量ROCKETMQ_HOME指向我的RocketMQ目录，结果还是一样。
ROCKETMQ_HOME=/home/rocketmq-all-4.7.1-bin-release