(Based on JDK 17)
jcmd Compiler.CodeHeap_Analytics
Print CodeHeap analytics
Syntax: Compiler.CodeHeap_Analytics [<function>] [<granularity>]
Arguments:
function : [optional] Function to be performed (aggregate, UsedSpace, FreeSpace, MethodCount, MethodSpace, MethodAge, MethodNames, discard (STRING, all)
granularity : [optional] Detail level - smaller value -> more detail (INT, 4096)
jcmd Compiler.codecache
Print code cache layout and bounds.
Syntax: Compiler.codecache
jcmd Compiler.codelist
Print all compiled methods in code cache that are alive
Syntax: Compiler.codelist
jcmd Compiler.directives_add
Add compiler directives from file.
Syntax: Compiler.directives_add <filename>
Arguments:
filename : Name of the directives file (STRING, no default value)
jcmd Compiler.directives_clear
Remove all compiler directives.
Syntax: Compiler.directives_clear
jcmd Compiler.directives_print
Print all active compiler directives.
Syntax: Compiler.directives_print
jcmd Compiler.directives_remove
Remove latest added compiler directive.
Syntax: Compiler.directives_remove
jcmd Compiler.perfmap
Write map file for Linux perf tool.
Syntax: Compiler.perfmap
jcmd Compiler.queue
Print methods queued for compilation.
Syntax: Compiler.queue
jcmd GC.class_histogram
Provide statistics about the Java heap usage.
Syntax: GC.class_histogram [options]
Options:
-all : [optional] Inspect all objects, including unreachable objects (BOOLEAN, false)
jcmd GC.finalizer_info
Provide information about Java finalization queue.
Syntax: GC.finalizer_info
jcmd GC.heap_dump
Generate a HPROF format dump of the Java heap.
Syntax: GC.heap_dump [options] <filename>
Arguments:
filename : Name of the dump file (STRING, no default value)
Options:
-all : [optional] Dump all objects, including unreachable objects (BOOLEAN, false)
-gz : [optional] If specified, the heap dump is written in gzipped format using the given compression level. 1 (recommended) is the fastest, 9 the strongest compression. (INT, 1)
jcmd GC.heap_info
Provide generic Java heap information.
Syntax: GC.heap_info
jcmd GC.run
Call java.lang.System.gc().
Syntax: GC.run
jcmd GC.run_finalization
Call java.lang.System.runFinalization().
Syntax: GC.run_finalization
jcmd JFR.check
Checks running JFR recording(s)
Syntax: JFR.check [options]
Options:
name : [optional] Recording name, e.g. \"My Recording\" or omit to see all recordings (STRING, no default value)
verbose : [optional] Print event settings for the recording(s) (BOOLEAN, false)
jcmd JFR.configure
Configure JFR
Syntax: JFR.configure [options]
Options:
repositorypath : [optional] Path to repository,.e.g \"My Repository\" (STRING, no default value)
dumppath : [optional] Path to dump,.e.g \"My Dump path\" (STRING, no default value)
stackdepth : [optional] Stack Depth (JULONG, 64)
globalbuffercount : [optional] Number of global buffers, (JULONG, 20)
globalbuffersize : [optional] Size of a global buffers, (MEMORY SIZE, 512k)
thread_buffer_size : [optional] Size of a thread buffer (MEMORY SIZE, 8k)
memorysize : [optional] Overall memory size, (MEMORY SIZE, 10m)
maxchunksize : [optional] Size of an individual disk chunk (MEMORY SIZE, 12m)
samplethreads : [optional] Activate Thread sampling (BOOLEAN, true)
jcmd JFR.dump
Copies contents of a JFR recording to file. Either the name or the recording id must be specified.
Syntax: JFR.dump [options]
Options:
name : [optional] Recording name, e.g. \"My Recording\" (STRING, no default value)
filename : [optional] Copy recording data to file, e.g. \"/home/user/My Recording.jfr\" (STRING, no default value)
maxage : [optional] Maximum duration to dump, in (s)econds, (m)inutes, (h)ours, or (d)ays, e.g. 60m, or 0 for no limit (NANOTIME, 0)
maxsize : [optional] Maximum amount of bytes to dump, in (M)B or (G)B, e.g. 500M, or 0 for no limit (MEMORY SIZE, 0)
begin : [optional] Point in time to dump data from, e.g. 09:00, 21:35:00, 2018-06-03T18:12:56.827Z, 2018-06-03T20:13:46.832, -10m, -3h, or -1d (STRING, no default value)
end : [optional] Point in time to dump data to, e.g. 09:00, 21:35:00, 2018-06-03T18:12:56.827Z, 2018-06-03T20:13:46.832, -10m, -3h, or -1d (STRING, no default value)
path-to-gc-roots : [optional] Collect path to GC roots (BOOLEAN, false)
jcmd JFR.start
Starts a new JFR recording
Syntax: JFR.start [options]
Options:
name : [optional] Name that can be used to identify recording, e.g. \"My Recording\" (STRING, no default value)
settings : [optional] Settings file(s), e.g. profile or default. See JAVA_HOME/lib/jfr (STRING SET, no default value)
delay : [optional] Delay recording start with (s)econds, (m)inutes), (h)ours), or (d)ays, e.g. 5h. (NANOTIME, 0)
duration : [optional] Duration of recording in (s)econds, (m)inutes, (h)ours, or (d)ays, e.g. 300s. (NANOTIME, 0)
disk : [optional] Recording should be persisted to disk (BOOLEAN, no default value)
filename : [optional] Resulting recording filename, e.g. \"/home/user/My Recording.jfr\" (STRING, no default value)
maxage : [optional] Maximum time to keep recorded data (on disk) in (s)econds, (m)inutes, (h)ours, or (d)ays, e.g. 60m, or 0 for no limit (NANOTIME, 0)
maxsize : [optional] Maximum amount of bytes to keep (on disk) in (k)B, (M)B or (G)B, e.g. 500M, or 0 for no limit (MEMORY SIZE, 0)
flush-interval : [optional] Minimum time before flushing buffers, measured in (s)econds, e.g. 4 s, or 0 for flushing when a recording ends (NANOTIME, 1s)
dumponexit : [optional] Dump running recording when JVM shuts down (BOOLEAN, no default value)
path-to-gc-roots : [optional] Collect path to GC roots (BOOLEAN, false)
jcmd JFR.stop
Stops a JFR recording
Syntax: JFR.stop [options]
Options:
name : Recording text,.e.g \"My Recording\" (STRING, no default value)
filename : [optional] Copy recording data to file, e.g. \"/home/user/My Recording.jfr\" (STRING, no default value)
jcmd JVMTI.agent_load
Load JVMTI native agent.
Syntax: JVMTI.agent_load <library path> [<agent option>]
Arguments:
library path : Absolute path of the JVMTI agent to load. (STRING, no default value)
agent option : [optional] Option string to pass the agent. (STRING, no default value)
jcmd JVMTI.data_dump
Signal the JVM to do a data-dump request for JVMTI.
Syntax: JVMTI.data_dump
jcmd ManagementAgent.start
Start remote management agent.
Syntax: ManagementAgent.start [options]
Options:
config.file : [optional] set com.sun.management.config.file (STRING, no default value)
jmxremote.host : [optional] set com.sun.management.jmxremote.host (STRING, no default value)
jmxremote.port : [optional] set com.sun.management.jmxremote.port (STRING, no default value)
jmxremote.rmi.port : [optional] set com.sun.management.jmxremote.rmi.port (STRING, no default value)
jmxremote.ssl : [optional] set com.sun.management.jmxremote.ssl (STRING, no default value)
jmxremote.registry.ssl : [optional] set com.sun.management.jmxremote.registry.ssl (STRING, no default value)
jmxremote.authenticate : [optional] set com.sun.management.jmxremote.authenticate (STRING, no default value)
jmxremote.password.file : [optional] set com.sun.management.jmxremote.password.file (STRING, no default value)
jmxremote.access.file : [optional] set com.sun.management.jmxremote.access.file (STRING, no default value)
jmxremote.login.config : [optional] set com.sun.management.jmxremote.login.config (STRING, no default value)
jmxremote.ssl.enabled.cipher.suites : [optional] set com.sun.management.jmxremote.ssl.enabled.cipher.suite (STRING, no default value)
jmxremote.ssl.enabled.protocols : [optional] set com.sun.management.jmxremote.ssl.enabled.protocols (STRING, no default value)
jmxremote.ssl.need.client.auth : [optional] set com.sun.management.jmxremote.need.client.auth (STRING, no default value)
jmxremote.ssl.config.file : [optional] set com.sun.management.jmxremote.ssl.config.file (STRING, no default value)
jmxremote.autodiscovery : [optional] set com.sun.management.jmxremote.autodiscovery (STRING, no default value)
jdp.port : [optional] set com.sun.management.jdp.port (INT, no default value)
jdp.address : [optional] set com.sun.management.jdp.address (STRING, no default value)
jdp.source_addr : [optional] set com.sun.management.jdp.source_addr (STRING, no default value)
jdp.ttl : [optional] set com.sun.management.jdp.ttl (INT, no default value)
jdp.pause : [optional] set com.sun.management.jdp.pause (INT, no default value)
jdp.name : [optional] set com.sun.management.jdp.name (STRING, no default value)
jcmd ManagementAgent.start_local
Start local management agent.
Syntax: ManagementAgent.start_local
jcmd ManagementAgent.status
Print the management agent status.
Syntax: ManagementAgent.status
jcmd ManagementAgent.stop
Stop remote management agent.
Syntax: ManagementAgent.stop
jcmd Thread.print
Print all threads with stacktraces.
Syntax: Thread.print [options]
Options:
-l : [optional] print java.util.concurrent locks (BOOLEAN, false)
-e : [optional] print extended thread information (BOOLEAN, false)
jcmd VM.class_hierarchy
Print a list of all loaded classes, indented to show the class hiearchy. The name of each class is followed by the ClassLoaderData* of its ClassLoader, or "null" if loaded by the bootstrap class loader.
Syntax: VM.class_hierarchy [options] [<classname>]
Arguments:
classname : [optional] Name of class whose hierarchy should be printed. If not specified, all class hierarchies are printed. (STRING, no default value)
Options:
-i : [optional] Inherited interfaces should be printed. (BOOLEAN, false)
-s : [optional] If a classname is specified, print its subclasses. Otherwise only its superclasses are printed. (BOOLEAN, false)
jcmd VM.classloader_stats
Print statistics about all ClassLoaders.
Syntax: VM.classloader_stats
jcmd VM.classloaders
Prints classloader hierarchy.
Syntax: VM.classloaders [options]
Options:
show-classes : [optional] Print loaded classes. (BOOLEAN, false)
verbose : [optional] Print detailed information. (BOOLEAN, false)
fold : Show loaders of the same name and class as one. (BOOLEAN, true)
jcmd VM.command_line
Print the command line used to start this VM instance.
Syntax: VM.command_line
jcmd VM.dynlibs
Print loaded dynamic libraries.
Syntax: VM.dynlibs
jcmd VM.events
Print VM event logs
Syntax: VM.events [options]
Options:
log : [optional] Name of log to be printed. If omitted, all logs are printed. (STRING, no default value)
max : [optional] Maximum number of events to be printed (newest first). If omitted, all events are printed. (STRING, no default value)
jcmd VM.flags
Print VM flag options and their current values.
Syntax: VM.flags [options]
Options:
-all : [optional] Print all flags supported by the VM (BOOLEAN, false)
jcmd VM.info
Print information about JVM environment and status.
Syntax: VM.info
jcmd VM.log
Lists current log configuration, enables/disables/configures a log output, or rotates all logs.
Syntax: VM.log [options]
Options:
output : [optional] The name or index (#<index>) of output to configure. (STRING, no default value)
output_options : [optional] Options for the output. (STRING, no default value)
what : [optional] Configures what tags to log. (STRING, no default value)
decorators : [optional] Configures which decorators to use. Use 'none' or an empty value to remove all. (STRING, no default value)
disable : [optional] Turns off all logging and clears the log configuration. (BOOLEAN, no default value)
list : [optional] Lists current log configuration. (BOOLEAN, no default value)
rotate : [optional] Rotates all logs. (BOOLEAN, no default value)
jcmd VM.metaspace
Prints the statistics for the metaspace
Syntax: VM.metaspace [options]
Options:
basic : [optional] Prints a basic summary (does not need a safepoint). (BOOLEAN, false)
show-loaders : [optional] Shows usage by class loader. (BOOLEAN, false)
show-classes : [optional] If show-loaders is set, shows loaded classes for each loader. (BOOLEAN, false)
by-chunktype : [optional] Break down numbers by chunk type. (BOOLEAN, false)
by-spacetype : [optional] Break down numbers by loader type. (BOOLEAN, false)
vslist : [optional] Shows details about the underlying virtual space. (BOOLEAN, false)
scale : [optional] Memory usage in which to scale. Valid values are: 1, KB, MB or GB (fixed scale) or "dynamic" for a dynamically choosen scale. (STRING, dynamic)
jcmd VM.native_memory
Print native memory usage
Syntax: VM.native_memory [options]
Options:
summary : [optional] request runtime to report current memory summary, which includes total reserved and committed memory, along with memory usage summary by each subsytem. (BOOLEAN, false)
detail : [optional] request runtime to report memory allocation >= 1K by each callsite. (BOOLEAN, false)
baseline : [optional] request runtime to baseline current memory usage, so it can be compared against in later time. (BOOLEAN, false)
summary.diff : [optional] request runtime to report memory summary comparison against previous baseline. (BOOLEAN, false)
detail.diff : [optional] request runtime to report memory detail comparison against previous baseline, which shows the memory allocation activities at different callsites. (BOOLEAN, false)
shutdown : [optional] request runtime to shutdown itself and free the memory used by runtime. (BOOLEAN, false)
statistics : [optional] print tracker statistics for tuning purpose. (BOOLEAN, false)
scale : [optional] Memory usage in which scale, KB, MB or GB (STRING, KB)
jcmd VM.print_touched_methods
Print all methods that have ever been touched during the lifetime of this JVM.
Syntax: VM.print_touched_methods
jcmd VM.set_flag
Sets VM flag option using the provided value.
Syntax: VM.set_flag <flag name> [<string value>]
Arguments:
flag name : The name of the flag we want to set (STRING, no default value)
string value : [optional] The value we want to set (STRING, no default value)
jcmd VM.stringtable
Dump string table.
Syntax: VM.stringtable [options]
Options:
-verbose : [optional] Dump the content of each string in the table (BOOLEAN, false)
jcmd VM.symboltable
Dump symbol table.
Syntax: VM.symboltable [options]
Options:
-verbose : [optional] Dump the content of each symbol in the table (BOOLEAN, false)
jcmd VM.system_properties
Print system properties.
Syntax: VM.system_properties
jcmd VM.systemdictionary
Prints the statistics for dictionary hashtable sizes and bucket length
Syntax: VM.systemdictionary [options]
Options:
-verbose : [optional] Dump the content of each dictionary entry for all class loaders (BOOLEAN, false)
jcmd VM.uptime
Print VM uptime.
Syntax: VM.uptime [options]
Options:
-date : [optional] Add a prefix with current date (BOOLEAN, false)
jcmd VM.version
Print JVM version information.
Syntax: VM.version