nodetool gcstats
Returns garbage collection statistics about all the garbage collection that has run since the last time nodetool gcstats was run.
Statistics include the following information:
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interval
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GC elapsed time (total and standard deviation)
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disk space reclaimed in megabytes (MB)
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number of garbage collections
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direct memory bytes
Synopsis
nodetool [<connection_options>] gcstats
Syntax legend
| Syntax conventions | Description |
|---|---|
Italic, bold, or |
Syntax diagrams and code samples use one or more of these styles to mark placeholders for variable values. Replace placeholders with a valid option or your own user-defined value. In CQL statements, angle brackets are required to enclose data types in a set, list, map, or tuple.
Separate the data types with a comma.
For example: In Search CQL statements, angle brackets are used to identify the entity and literal value to overwrite the XML element in the schema and |
|
Square brackets surround optional command arguments. Do not type the square brackets. |
|
Parentheses identify a group to choose from. Do not type the parentheses. |
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A pipe separates alternative elements. Type any one of the elements. Do not type the pipe. |
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Indicates that you can repeat the syntax element as often as required. |
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Single quotation marks must surround literal strings in CQL statements.
Use single quotation marks to preserve upper case.
+
For Search CQL only: Single quotation marks surround an entire XML schema declaration, such as |
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Map collection.
Curly braces enclose maps ( |
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Ends a CQL statement. |
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Separate command line options from command arguments with two hyphens. This syntax is useful when arguments might be mistaken for command line options. |
Options
If an option has a short and long form, both forms are given, separated by a comma.
- -h, --host hostname
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The hostname or IP address of a remote node or nodes. When omitted, the default is the local machine.
- -p, --port jmx_port
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The JMX port number.
- -pw, --password jmxpassword
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The JMX password for authenticating with secure JMX. If a password is not provided, you are prompted to enter one.
- -pwf, --password-file jmx_password_filepath
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The filepath to the file that stores JMX authentication credentials.
- -u, --username jmx_username
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The username for authenticating with secure JMX.
Examples
To print garbage collection statistics:
nodetool gcstats
Results:
Interval (ms) Max GC Elapsed (ms)Total GC Elapsed (ms)Stdev GC Elapsed (ms) GC Reclaimed (MB) Collections Direct Memory Bytes
520255260 350 43299 24 1231539 1108 220182597</codeblock></section>