[ElasticSearch] ommit_memory(0x0000000085330000, 2060255232, 0) failed; error='Cannot allocate memor

ElasticSearch 5.1.1 在启动过程中报错

OpenJDK 64-Bit Server VM warning: If the number of processors is expected to increase from one, then you should configure the number of parallel GC threads appropriately using -XX:ParallelGCThreads=N
OpenJDK 64-Bit Server VM warning: INFO: os::commit_memory(0x0000000085330000, 2060255232, 0) failed; error='Cannot allocate memory' (errno=12)
#
# There is insufficient memory for the Java Runtime Environment to continue.
# Native memory allocation (mmap) failed to map 2060255232 bytes for committing reserved memory.
# An error report file with more information is saved as:
# /root/elasticsearch-5.5.1/hs_err_pid7450.log

因为默认 ElasticSearch 分配内存是 2 G，但是由于电脑不够所以启动不了。可以通过修改内存来启动.

在 elasticSearch 文件夹下，输入命令行

vim config/jvm.options 

将参数调为 512 m

-Xms512m

-Xmx512m

因为内存无法启动的问题可以解决了。

如果还出现这样的错误

OpenJDK 64-Bit Server VM warning: If the number of processors is expected to increase from one, then you should configure the number of parallel GC threads appropriately using -XX:ParallelGCThreads=N
[2018-12-11T12:53:33,473][WARN ][o.e.b.ElasticsearchUncaughtExceptionHandler] [] uncaught exception in thread [main]
org.elasticsearch.bootstrap.StartupException: java.lang.RuntimeException: can not run elasticsearch as root
	at org.elasticsearch.bootstrap.Elasticsearch.init(Elasticsearch.java:127) ~[elasticsearch-5.5.1.jar:5.5.1]
	at org.elasticsearch.bootstrap.Elasticsearch.execute(Elasticsearch.java:114) ~[elasticsearch-5.5.1.jar:5.5.1]
	at org.elasticsearch.cli.EnvironmentAwareCommand.execute(EnvironmentAwareCommand.java:67) ~[elasticsearch-5.5.1.jar:5.5.1]
	at org.elasticsearch.cli.Command.mainWithoutErrorHandling(Command.java:122) ~[elasticsearch-5.5.1.jar:5.5.1]
	at org.elasticsearch.cli.Command.main(Command.java:88) ~[elasticsearch-5.5.1.jar:5.5.1]
	at org.elasticsearch.bootstrap.Elasticsearch.main(Elasticsearch.java:91) ~[elasticsearch-5.5.1.jar:5.5.1]
	at org.elasticsearch.bootstrap.Elasticsearch.main(Elasticsearch.java:84) ~[elasticsearch-5.5.1.jar:5.5.1]
Caused by: java.lang.RuntimeException: can not run elasticsearch as root
	at org.elasticsearch.bootstrap.Bootstrap.initializeNatives(Bootstrap.java:106) ~[elasticsearch-5.5.1.jar:5.5.1]
	at org.elasticsearch.bootstrap.Bootstrap.setup(Bootstrap.java:194) ~[elasticsearch-5.5.1.jar:5.5.1]
	at org.elasticsearch.bootstrap.Bootstrap.init(Bootstrap.java:351) ~[elasticsearch-5.5.1.jar:5.5.1]
	at org.elasticsearch.bootstrap.Elasticsearch.init(Elasticsearch.java:123) ~[elasticsearch-5.5.1.jar:5.5.1]
	... 6 more

那是因为 elasticSearch 不允许你直接通过 root 来登陆。所以年纪需要另外设置一个账户来启动的它。

adduser es

passwd es

chown -R es:es elasticsearch-5.1.1/

chmod 770 elasticsearch-5.1.1/

然后使用 es 用户登陆，重新启动 elasticSearch 即可。