83 lines
2.9 KiB
Plaintext
83 lines
2.9 KiB
Plaintext
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[[jvm-options]]
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=== Setting JVM options
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The preferred method of setting JVM options (including system properties and JVM
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flags) is via the `jvm.options` configuration file. The default location of this
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file is `config/jvm.options` (when installing from the tar or zip distributions)
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and `/etc/elasticsearch/jvm.options` (when installing from the Debian or RPM
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packages).
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This file contains a line-delimited list of JVM arguments following
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a special syntax:
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* lines consisting of whitespace only are ignored
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* lines beginning with `#` are treated as comments and are ignored
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+
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[source,text]
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-------------------------------------
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# this is a comment
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-------------------------------------
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* lines beginning with a `-` are treated as a JVM option that applies
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independent of the version of the JVM
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+
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[source,text]
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-------------------------------------
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-Xmx2g
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-------------------------------------
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* lines beginning with a number followed by a `:` followed by a `-` are treated
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as a JVM option that applies only if the version of the JVM matches the number
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+
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[source,text]
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-------------------------------------
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8:-Xmx2g
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-------------------------------------
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* lines beginning with a number followed by a `-` followed by a `:` are treated
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as a JVM option that applies only if the version of the JVM is greater than or
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equal to the number
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+
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[source,text]
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-------------------------------------
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8-:-Xmx2g
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-------------------------------------
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* lines beginning with a number followed by a `-` followed by a number followed
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by a `:` are treated as a JVM option that applies only if the version of the
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JVM falls in the range of the two numbers
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+
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[source,text]
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-------------------------------------
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8-9:-Xmx2g
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-------------------------------------
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* all other lines are rejected
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You can add custom JVM flags to this file and check this configuration into your
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version control system.
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An alternative mechanism for setting Java Virtual Machine options is via the
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`ES_JAVA_OPTS` environment variable. For instance:
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[source,sh]
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---------------------------------
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export ES_JAVA_OPTS="$ES_JAVA_OPTS -Djava.io.tmpdir=/path/to/temp/dir"
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./bin/elasticsearch
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---------------------------------
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When using the RPM or Debian packages, `ES_JAVA_OPTS` can be specified in the
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<<sysconfig,system configuration file>>.
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The JVM has a built-in mechanism for observing the `JAVA_TOOL_OPTIONS`
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environment variable. We intentionally ignore this environment variable in our
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packaging scripts. The primary reason for this is that on some OS (e.g., Ubuntu)
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there are agents installed by default via this environment variable that we do
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not want interfering with Elasticsearch.
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Additionally, some other Java programs support the `JAVA_OPTS` environment
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variable. This is *not* a mechanism built into the JVM but instead a convention
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in the ecosystem. However, we do not support this environment variable, instead
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supporting setting JVM options via the `jvm.options` file or the environment
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variable `ES_JAVA_OPTS` as above.
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