nodetool gcstats

Print garbage collection (GC) statistics.

Synopsis

nodetool [options] gcstats

Cassandra tarball installations:

installation_location/cassandra/bin

Table 1. Options
Short	Long	Description
`-h`	`--host`	Hostname or IP address.
`-p`	`--port`	Port number.
`-pwf`	`--password-file`	Password file path.
`-pw`	`--password`	Password.
`-u`	`--username`	Remote JMX agent username.
`--`	Separates an option from an argument that could be mistaken for a option.

Note:

For tarball installations, execute the command from the install_location/bin directory.
If a username and password for RMI authentication are set explicitly in the cassandra-env.sh file for the host, then you must specify credentials.
nodetool gcstats operates on a single node in the cluster if -h is not used to identify one or more other nodes. If the node from which you issue the command is the intended target, you do not need the -h option to identify the target; otherwise, for remote invocation, identify the target node, or nodes, using -h.

Description

The nodetool gcstats command will print garbage collection statistics that returns values based on all the garbage collection that has run since the last time nodetool gcstats was run. Statistics identify the interval time, some GC elapsed time measures, the disk space reclaimed (in MB), number of garbage collections that took place, and direct memory bytes.

Examples

nodetool -u cassandra -pw cassandra gcstats

The location of the cassandra-env.sh file depends on the type of installation:

Cassandra package installations	/etc/cassandra/cassandra-env.sh
Cassandra tarball installations	`install_location`/conf/cassandra-env.sh