在我的/etc/elasticsearch/jvm.options
我已经使用以下命令设置了堆大小：
-Xms256m
-Xmx256m
但是，当我重新启动服务时，内存不断上升，直到用完为止，然后服务突然停止：
[root@st2 elasticsearch]# sudo systemctl status elasticsearch
● elasticsearch.service - Elasticsearch
Loaded: loaded (/usr/lib/systemd/system/elasticsearch.service; enabled; vendor preset: disabled)
Active: active (running) since Fri 2019-06-14 14:05:15 UTC; 7s ago
Docs: http://www.elastic.co
Main PID: 20280 (java)
Tasks: 22
Memory: 486.6M
CGroup: /system.slice/elasticsearch.service
├─20280 /bin/java -Xms256m -Xmx256m -XX:+UseConcMarkSweepGC -XX:CMSInitiatingOccupan...
└─20359 /usr/share/elasticsearch/modules/x-pack-ml/platform/linux-x86_64/bin/control..
我正在使用centos：
[root@st2 elasticsearch]# cat /etc/centos-release
CentOS Linux release 7.6.1810 (Core)
更多信息：
系统服务
[root@st2 elasticsearch]# systemctl cat elasticsearch
# /usr/lib/systemd/system/elasticsearch.service
[Unit]
Description=Elasticsearch
Documentation=http://www.elastic.co
Wants=network-online.target
After=network-online.target
[Service]
RuntimeDirectory=elasticsearch
PrivateTmp=true
Environment=ES_HOME=/usr/share/elasticsearch
Environment=ES_PATH_CONF=/etc/elasticsearch
Environment=PID_DIR=/var/run/elasticsearch
Environment=ES_HEAP_SIZE=256M
EnvironmentFile=-/etc/sysconfig/elasticsearch
WorkingDirectory=/usr/share/elasticsearch
User=elasticsearch
Group=elasticsearch
ExecStart=/usr/share/elasticsearch/bin/elasticsearch -p ${PID_DIR}/elasticsearch.pid --quiet
# StandardOutput is configured to redirect to journalctl since
# some error messages may be logged in standard output before
# elasticsearch logging system is initialized. Elasticsearch
# stores its logs in /var/log/elasticsearch and does not use
# journalctl by default. If you also want to enable journalctl
# logging, you can simply remove the "quiet" option from ExecStart.
StandardOutput=journal
StandardError=inherit
# Specifies the maximum file descriptor number that can be opened by this process
LimitNOFILE=65535
# Specifies the maximum number of processes
LimitNPROC=4096
# Specifies the maximum size of virtual memory
LimitAS=infinity
# Specifies the maximum file size
LimitFSIZE=infinity
# Disable timeout logic and wait until process is stopped
TimeoutStopSec=0
# SIGTERM signal is used to stop the Java process
/etc/elasticsearch/jvm.options
## 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
-Xms256m
-Xmx256m
################################################################
## 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
-XX:+UseConcMarkSweepGC
-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=/var/lib/elasticsearch
# specify an alternative path for JVM fatal error logs
-XX:ErrorFile=/var/log/elasticsearch/hs_err_pid%p.log
## JDK 8 GC logging
8:-XX:+PrintGCDetails
8:-XX:+PrintGCDateStamps
8:-XX:+PrintTenuringDistribution
8:-XX:+PrintGCApplicationStoppedTime
8:-Xloggc:/var/log/elasticsearch/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=/var/log/elasticsearch/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
# temporary workaround for C2 bug with JDK 10 on hardware with AVX-512
10-:-XX:UseAVX=2