Elasticsearch7.2启动指定JDK11

环境说明

Centos7、Elasticsearch7.2、JAVA_HOME="/opt/jdk1.8.0_211"

前篇提要

Centos7安装Elasticsearch7.2版本
前面我们说到，我的虚拟机开发环境的jdk是1.8，在启动Elasticsearch7.2的时候，启动日志会有如下信息：

future versions of Elasticsearch will require Java 11; your Java version from [/opt/jdk1.8.0_211/jre] does not meet this requirement

这是由于Elasticsearch依赖于jdk，es和jdk有着对应的依赖关系。具体可见：
https://www.elastic.co/cn/support/matrix
https://www.elastic.co/guide/en/elasticsearch/reference/7.2/setup.html

image.png
这里是说Elasticsearch该版本内置了JDK，而内置的JDK是当前推荐的JDK版本。当然如果你本地配置了JAVA_HOME那么ES就是优先使用配置的JDK启动ES。（言外之意，你不安装JDK一样可以启动，我试了可以的。）
ES推荐使用LTS版本的JDK（这里只是推荐，JDK8就不支持），如果你使用了一些不支持的JDK版本，ES会拒绝启动。

那么哪些版本的JDK支持LTS呢？https://www.oracle.com/technetwork/java/java-se-support-roadmap.html

image.png

根据启动信息我们看到Elasticsearch7.2推荐使用JDK11，并且从刚才的截图得知可以下载openjdk 11.

安装OpenJDK11

下载安装包

[root@localhost tar.gz]# pwd
/usr/local/src/tar.gz
[root@localhost tar.gz]# wget https://download.java.net/java/GA/jdk11/13/GPL/openjdk-11.0.1_linux-x64_bin.tar.gz

百度云
链接：https://pan.baidu.com/s/1wneFxHIcjzbUsQYrfhgi6Q
提取码：nfld

解压到指定目录

[root@localhost tar.gz]# tar -xzvf jdk-11.0.4_linux-x64_bin.tar.gz /opt/

到此结束
由于我们日常的代码开发都是使用的JDK1.8，所以这里不会把JAVA_HOME配置成JDK11，我们只需更改Elasticsearch的启动文件，使它指向我们下载的JDK11.

修改配置文件
[root@localhost bin]# pwd
/usr/local/src/elasticsearch/bin
[root@localhost bin]# vi elasticsearch
添加一下几行内容

#配置自己的jdk11
export JAVA_HOME=/opt/jdk-11.0.1
export PATH=$JAVA_HOME/bin:$PATH


#添加jdk判断
if [ -x "$JAVA_HOME/bin/java" ]; then
        JAVA="/opt/jdk-11.0.1/bin/java"
else
        JAVA=`which java`
fi

为了方便大家参考，这里贴上完整的配置文件

#!/bin/bash

# CONTROLLING STARTUP:
#
# This script relies on a few environment variables to determine startup
# behavior, those variables are:
#
#   ES_PATH_CONF -- Path to config directory
#   ES_JAVA_OPTS -- External Java Opts on top of the defaults set
#
# Optionally, exact memory values can be set using the `ES_JAVA_OPTS`. Note that
# the Xms and Xmx lines in the JVM options file must be commented out. Example
# values are "512m", and "10g".
#
#   ES_JAVA_OPTS="-Xms8g -Xmx8g" ./bin/elasticsearch

#配置自己的jdk11
export JAVA_HOME=/opt/jdk-11.0.1
export PATH=$JAVA_HOME/bin:$PATH

source "`dirname "$0"`"/elasticsearch-env

if [ -z "$ES_TMPDIR" ]; then
  ES_TMPDIR=`"$JAVA" -cp "$ES_CLASSPATH" org.elasticsearch.tools.launchers.TempDirectory`
fi

ES_JVM_OPTIONS="$ES_PATH_CONF"/jvm.options
JVM_OPTIONS=`"$JAVA" -cp "$ES_CLASSPATH" org.elasticsearch.tools.launchers.JvmOptionsParser "$ES_JVM_OPTIONS"`
ES_JAVA_OPTS="${JVM_OPTIONS//\$\{ES_TMPDIR\}/$ES_TMPDIR}"

#添加jdk判断
if [ -x "$JAVA_HOME/bin/java" ]; then
        JAVA="/opt/jdk-11.0.1/bin/java"
else
        JAVA=`which java`
fi

# manual parsing to find out, if process should be detached
if ! echo $* | grep -E '(^-d |-d$| -d |--daemonize$|--daemonize )' > /dev/null; then
  exec \
    "$JAVA" \
    $ES_JAVA_OPTS \
    -Des.path.home="$ES_HOME" \
    -Des.path.conf="$ES_PATH_CONF" \
    -Des.distribution.flavor="$ES_DISTRIBUTION_FLAVOR" \
    -Des.distribution.type="$ES_DISTRIBUTION_TYPE" \
    -Des.bundled_jdk="$ES_BUNDLED_JDK" \
    -cp "$ES_CLASSPATH" \
    org.elasticsearch.bootstrap.Elasticsearch \
    "$@"
else
  exec \
    "$JAVA" \
    $ES_JAVA_OPTS \
    -Des.path.home="$ES_HOME" \
    -Des.path.conf="$ES_PATH_CONF" \
    -Des.distribution.flavor="$ES_DISTRIBUTION_FLAVOR" \
    -Des.distribution.type="$ES_DISTRIBUTION_TYPE" \
    -Des.bundled_jdk="$ES_BUNDLED_JDK" \
    -cp "$ES_CLASSPATH" \
    org.elasticsearch.bootstrap.Elasticsearch \
    "$@" \
    <&- &
  retval=$?
  pid=$!
  [ $retval -eq 0 ] || exit $retval
  if [ ! -z "$ES_STARTUP_SLEEP_TIME" ]; then
    sleep $ES_STARTUP_SLEEP_TIME
  fi
  if ! ps -p $pid > /dev/null ; then
    exit 1
  fi
  exit 0
fi

exit $?

启动ES

[esuser@localhost bin]$ ./elasticsearch
OpenJDK 64-Bit Server VM warning: Option UseConcMarkSweepGC was deprecated in version 9.0 and will likely be removed in a future release.
[2019-08-02T15:33:27,994][INFO ][o.e.e.NodeEnvironment    ] [node-1] using [1] data paths, mounts [[/ (rootfs)]], net usable_space [32.6gb], net total_space [35.7gb], types [rootfs]
[2019-08-02T15:33:28,014][INFO ][o.e.e.NodeEnvironment    ] [node-1] heap size [1015.6mb], compressed ordinary object pointers [true]
[2019-08-02T15:33:28,017][INFO ][o.e.n.Node               ] [node-1] node name [node-1], node ID [8zGCWQhBS3OpVShqjSgU-w], cluster name [es-application]
[2019-08-02T15:33:28,017][INFO ][o.e.n.Node               ] [node-1] version[7.2.0], pid[1545], build[default/tar/508c38a/2019-06-20T15:54:18.811730Z], OS[Linux/3.10.0-862.el7.x86_64/amd64], JVM[Oracle Corporation/OpenJDK 64-Bit Server VM/11.0.1/11.0.1+13]
[2019-08-02T15:33:28,017][INFO ][o.e.n.Node               ] [node-1] JVM home [/opt/jdk-11.0.1]
[2019-08-02T15:33:28,018][INFO ][o.e.n.Node               ] [node-1] JVM arguments [-Xms1g, -Xmx1g, -XX:+UseConcMarkSweepGC, -XX:CMSInitiatingOccupancyFraction=75, -XX:+UseCMSInitiatingOccupancyOnly, -Des.networkaddress.cache.ttl=60, -Des.networkaddress.cache.negative.ttl=10, -XX:+AlwaysPreTouch, -Xss1m, -Djava.awt.headless=true, -Dfile.encoding=UTF-8, -Djna.nosys=true, -XX:-OmitStackTraceInFastThrow, -Dio.netty.noUnsafe=true, -Dio.netty.noKeySetOptimization=true, -Dio.netty.recycler.maxCapacityPerThread=0, -Dlog4j.shutdownHookEnabled=false, -Dlog4j2.disable.jmx=true, -Djava.io.tmpdir=/tmp/elasticsearch-5247006010869253587, -XX:+HeapDumpOnOutOfMemoryError, -XX:HeapDumpPath=data, -XX:ErrorFile=logs/hs_err_pid%p.log, -Xlog:gc*,gc+age=trace,safepoint:file=logs/gc.log:utctime,pid,tags:filecount=32,filesize=64m, -Djava.locale.providers=COMPAT, -Dio.netty.allocator.type=unpooled, -XX:MaxDirectMemorySize=536870912, -Des.path.home=/usr/local/src/elasticsearch, -Des.path.conf=/usr/local/src/elasticsearch/config, -Des.distribution.flavor=default, -Des.distribution.type=tar, -Des.bundled_jdk=true]

到这里我们又看到另一个警告

OpenJDK 64-Bit Server VM warning: Option UseConcMarkSweepGC was deprecated in version 9.0 and will likely be removed in a future release.
这是提醒你 cms 垃圾收集器在 jdk9 就开始被标注为 @deprecated

看下JDK11支持的垃圾回收器
HotSpot Virtual Machine Garbage Collection Tuning Guide

image.png

修改jvm.options
将 ：
改为：-XX:+UseG1GC

完整配置如下

## JVM configuration

################################################################
## IMPORTANT: JVM heap size
################################################################
##
## You should always set the min and max JVM heap
## size to the same value. For example, to set
## the heap to 4 GB, set:
##
## -Xms4g
## -Xmx4g
##
## See https://www.elastic.co/guide/en/elasticsearch/reference/current/heap-size.html
## for more information
##
################################################################

# Xms represents the initial size of total heap space
# Xmx represents the maximum size of total heap space

-Xms1g
-Xmx1g

################################################################
## Expert settings
################################################################
##
## All settings below this section are considered
## expert settings. Don't tamper with them unless
## you understand what you are doing
##
################################################################

## GC configuration
## 原有的注释了，添加了G1回收器
## -XX:+UseConcMarkSweepGC
-XX:+UseG1GC
-XX:CMSInitiatingOccupancyFraction=75
-XX:+UseCMSInitiatingOccupancyOnly

## G1GC Configuration
# NOTE: G1GC is only supported on JDK version 10 or later.
# To use G1GC uncomment the lines below.
# 10-:-XX:-UseConcMarkSweepGC
# 10-:-XX:-UseCMSInitiatingOccupancyOnly
# 10-:-XX:+UseG1GC
# 10-:-XX:InitiatingHeapOccupancyPercent=75

## DNS cache policy
# cache ttl in seconds for positive DNS lookups noting that this overrides the
# JDK security property networkaddress.cache.ttl; set to -1 to cache forever
-Des.networkaddress.cache.ttl=60
# cache ttl in seconds for negative DNS lookups noting that this overrides the
# JDK security property networkaddress.cache.negative ttl; set to -1 to cache
# forever
-Des.networkaddress.cache.negative.ttl=10

## optimizations

# pre-touch memory pages used by the JVM during initialization
-XX:+AlwaysPreTouch

## basic

# explicitly set the stack size
-Xss1m

# set to headless, just in case
-Djava.awt.headless=true

# ensure UTF-8 encoding by default (e.g. filenames)
-Dfile.encoding=UTF-8

# use our provided JNA always versus the system one
-Djna.nosys=true

# turn off a JDK optimization that throws away stack traces for common
# exceptions because stack traces are important for debugging
-XX:-OmitStackTraceInFastThrow

# flags to configure Netty
-Dio.netty.noUnsafe=true
-Dio.netty.noKeySetOptimization=true
-Dio.netty.recycler.maxCapacityPerThread=0

# log4j 2
-Dlog4j.shutdownHookEnabled=false
-Dlog4j2.disable.jmx=true

-Djava.io.tmpdir=${ES_TMPDIR}

## heap dumps

# generate a heap dump when an allocation from the Java heap fails
# heap dumps are created in the working directory of the JVM
-XX:+HeapDumpOnOutOfMemoryError

# specify an alternative path for heap dumps; ensure the directory exists and
# has sufficient space
-XX:HeapDumpPath=data

# specify an alternative path for JVM fatal error logs
-XX:ErrorFile=logs/hs_err_pid%p.log

## JDK 8 GC logging

8:-XX:+PrintGCDetails
8:-XX:+PrintGCDateStamps
8:-XX:+PrintTenuringDistribution
8:-XX:+PrintGCApplicationStoppedTime
8:-Xloggc:logs/gc.log
8:-XX:+UseGCLogFileRotation
8:-XX:NumberOfGCLogFiles=32
8:-XX:GCLogFileSize=64m

# JDK 9+ GC logging
9-:-Xlog:gc*,gc+age=trace,safepoint:file=logs/gc.log:utctime,pid,tags:filecount=32,filesize=64m
# due to internationalization enhancements in JDK 9 Elasticsearch need to set the provider to COMPAT otherwise
# time/date parsing will break in an incompatible way for some date patterns and locals
9-:-Djava.locale.providers=COMPAT

保存重新启动

[esuser@localhost bin]$ ./elasticsearch
[2019-08-02T15:58:33,923][INFO ][o.e.e.NodeEnvironment    ] [node-1] using [1] data paths, mounts [[/ (rootfs)]], net usable_space [32.6gb], net total_space [35.7gb], types [rootfs]
[2019-08-02T15:58:33,951][INFO ][o.e.e.NodeEnvironment    ] [node-1] heap size [1gb], compressed ordinary object pointers [true]
[2019-08-02T15:58:33,953][INFO ][o.e.n.Node               ] [node-1] node name [node-1], node ID [8zGCWQhBS3OpVShqjSgU-w], cluster name [es-application]
[2019-08-02T15:58:33,953][INFO ][o.e.n.Node               ] [node-1] version[7.2.0], pid[1700], build[default/tar/508c38a/2019-06-20T15:54:18.811730Z], OS[Linux/3.10.0-862.el7.x86_64/amd64], JVM[Oracle Corporation/OpenJDK 64-Bit Server VM/11.0.1/11.0.1+13]
[2019-08-02T15:58:33,954][INFO ][o.e.n.Node               ] [node-1] JVM home [/opt/jdk-11.0.1]
[2019-08-02T15:58:33,954][INFO ][o.e.n.Node               ] [node-1] JVM arguments [-Xms1g, -Xmx1g, -XX:+UseG1GC, -XX:CMSInitiatingOccupancyFraction=75, -XX:+UseCMSInitiatingOccupancyOnly, -Des.networkaddress.cache.ttl=60, -Des.networkaddress.cache.negative.ttl=10, -XX:+AlwaysPreTouch, -Xss1m, -Djava.awt.headless=true, -Dfile.encoding=UTF-8, -Djna.nosys=true, -XX:-OmitStackTraceInFastThrow, -Dio.netty.noUnsafe=true, -Dio.netty.noKeySetOptimization=true, -Dio.netty.recycler.maxCapacityPerThread=0, -Dlog4j.shutdownHookEnabled=false, -Dlog4j2.disable.jmx=true, -Djava.io.tmpdir=/tmp/elasticsearch-15008659954472371205, -XX:+HeapDumpOnOutOfMemoryError, -XX:HeapDumpPath=data, -XX:ErrorFile=logs/hs_err_pid%p.log, -Xlog:gc*,gc+age=trace,safepoint:file=logs/gc.log:utctime,pid,tags:filecount=32,filesize=64m, -Djava.locale.providers=COMPAT, -Dio.netty.allocator.type=unpooled, -XX:MaxDirectMemorySize=536870912, -Des.path.home=/usr/local/src/elasticsearch, -Des.path.conf=/usr/local/src/elasticsearch/config, -Des.distribution.flavor=default, -Des.distribution.type=tar, -Des.bundled_jdk=true]

警告消失了