JCMD(1) JDK Commands JCMD(1) (NAME) jcmd - (JVM) (SYNOPSIS) jcmd [pid | main-class] command... | PerfCounter.print | -f filename jcmd [-l] jcmd -h pid jcmd (PID) . main-class jcmd . command command jcmd JVM . jcmd help (jcmd pid help) pid . Perfcounter.print . -f filename filename . -l docker . JVM docker ps PID . : jcmd jcmd -l . -h jcmd . (DESCRIPTION) jcmd JVM . JVM JVM . . . : jcmd pid help command (' ") . (\) . ( ). (pid) (main-class) jcmd . 0 . JCMD (COMMANDS FOR JCMD) command jcmd JVM . jcmd help (jcmd pid help) pid . pid 0 . . docker ( -l). jcmd . key key=value . name=value . : help [options] [arguments] . : o command name: (STRING ) : key key=value . : o -all: () (BOOLEAN false) . AOT.end_recording AOT () -XX:AOTConfiguration / -XX:AOTCacheOutput . : : (JVM) -XX:AOTMode=record -XX:AOTCacheOutput= AOT . AOT AOT (cache) AOT . Compiler.CodeHeap_Analytics [function] [granularity] CodeHeap : : (code heap) . CodeCache_lock . : o function: () (aggregate UsedSpace FreeSpace MethodCount MethodSpace MethodAge MethodNames discard) (STRING all) o granularity: () - -> (INT 4096) Compiler.codecache (code cache) . : Compiler.codelist (code cache) . : Compiler.directives_add arguments . : : o filename: (STRING ) Compiler.directives_clear . : Compiler.directives_print . : Compiler.directives_remove . : Compiler.memory [options] : : : key key=value . : o -H: () (BOOLEAN false).IP o 2 -s: () (MEMORY SIZE, 0) Compiler.perfmap [] ( ) (map) perf . : : o filename: () . %p PID JVM . (FILE, "/tmp/perf-%p.map") Compiler.queue . : GC.class_histogram [] heap . : --- heap . : key key=value . : o -all: () (BOOLEAN, false) o -parallel: () heap. 0 () VM . 1 ( ). VM . (INT, 0) GC.finalizer_info finalization . : GC.heap_dump [] filename dump HPROF heap . : --- heap . GC -all . : key key=value . : o -all: () (dump) (BOOLEAN, false) o -gz: () heap dump gzip . 1 () 9 . (INT, 1) o -overwrite: () dump (BOOLEAN, false) o -parallel: () heap dump. (VM) . (INT, 1) : o filename: dump. %p PID JVM . (FILE, ) GC.heap_info heap . : GC.run java.lang.System.gc() . : --- heap . GC.run_finalization java.lang.System.runFinalization() . : --- . JFR.check [] flight recording : : key key=value . . : o name: () flight recording. (STRING, ) o verbose: () (BOOLEAN, false) JFR.configure [] flight recording : : key key=value . . : o dumppath: () VM ( ) . (STRING, ) o globalbuffercount: () (global buffers). (legacy) : memorysize . JFR . (STRING, memorysize ) o globalbuffersize: () . (legacy) : memorysize . JFR . (STRING, memorysize ) o maxchunksize: () (data chunk) : 'm' 'M' 'g' 'G' . JFR . (STRING, 12M) o memorysize: () : 'm' 'M' 'g' 'G' . JFR . (STRING, 10M) o repositorypath: () . (STRING, . /tmp . TMP .) o preserve-repository={true|false} : JVM . false . . o stackdepth: () (stack traces). 64 . JFR . (LONG, 64) o thread_buffer_size: () : 'k' 'K' 'm' 'M' . . JFR . (STRING, 8k) o samplethreads: () (thread sampling). (BOOLEAN, true) JFR.dump [] flight recording : : key key=value . . . :.IP o 2 begin: () (dump) . . (STRING ) o end: () (dump) . . (STRING ) : begin end java.time.LocalTime::parse(STRING) java.time.LocalDateTime::parse(STRING) java.time.Instant::parse(STRING) . "13:20:15" "2020-03-17T09:00:00" "2020-03-17T09:00:00Z". : begin end (timestamps) flight recording . "s" "m" "h" . "-12h" "-15m" "-30s". o filename: () flight recording (dump) . PID . PID . %p / %t PID JVM . (FILE ) o maxage: () flight recording . (INTEGER 's' 'm' 'h' ) o maxsize: () flight recording : 'm' 'M' 'g' 'G' . (STRING ) o name: () . . (STRING ) o path-to-gc-roots: () (GC) . (memory leaks) . . (BOOLEAN false) JFR.start [options] flight recording : : options key key=value . . options: o delay: () (INTEGER 's' 'm' 'h' 0s) o disk: () (BOOLEAN true) o dumponexit: () (JVM). 'true' filename . (PID) . ( : id-1-2019_12_12_10_41.jfr) (BOOLEAN false) o duration: () . 0s () (INTEGER 's' 'm' 'h' 0s) o filename: () flight recording . PID . PID . %p / %t PID JVM . (FILE ) o maxage: () . disk true . 0s () . (INTEGER 's' 'm' 'h' 0s) o maxsize: () : 'm' 'M' 'g' 'G' . disk 'true' . maxchunksize JFR.configure . (STRING 0 ( )) o name: () . . . (STRING ) o path-to-gc-roots: () (GC) . . . settings 'profile' (stack trace) . (BOOLEAN false) o settings: () . (',') . JAVA-HOME/lib/jfr . JDK JAVA-HOME/lib/jfr : 'default.jfc': (overhead) 'profile.jfc': 'default.jfc' . . none . (STRING JAVA-HOME/lib/jfr/default.jfc) .jfc : o option: () . JAVA_HOME/bin/jfr . o event-setting: () . : #= '+' . .jfc (whitespace) . .jfc . 20ms. Javadoc jdk.jfr . JFR.stop [options] flight recording : : options key key=value . . options: o filename: () . %p / %t PID JVM . . (FILE ) o name: () (STRING ) JFR.view [options] . : : options key key=value . . options:.IP o 2 cell-height: () . (INT ) o maxage: () . (INT 's' 'm' 'h' 10m ) o maxsize: () : 'm' 'M' 'g' 'G' . (STRING 32MB ) o truncate: () . (INT ) o verbose: () . (BOOLEAN false ) o width: () . (INT ) : o view: . help JFR.view . (STRING ) view . JFR.view types . JFR.view all-views . JFR.view all-events . JVMTI.agent_load [] JVMTI . : : o library path: JVMTI . (STRING ) o agent option: () . (STRING ) JVMTI.data_dump JVM data-dump JVMTI . : ManagementAgent.start [] . : --- : key key=value . : o config.file: () com.sun.management.config.file (STRING ) o jmxremote.host: () com.sun.management.jmxremote.host (STRING ) o jmxremote.port: () com.sun.management.jmxremote.port (STRING ) o jmxremote.rmi.port: () com.sun.management.jmxremote.rmi.port (STRING ) o jmxremote.ssl: () com.sun.management.jmxremote.ssl (STRING ) o jmxremote.registry.ssl: () com.sun.management.jmxremote.registry.ssl (STRING ) o jmxremote.authenticate: () com.sun.management.jmxremote.authenticate (STRING ) o jmxremote.password.file: () com.sun.management.jmxremote.password.file (STRING ) o jmxremote.access.file: () com.sun.management.jmxremote.acce ss.file (STRING ) o jmxremote.login.config: () com.sun.management.jmxremote.log in.config (STRING ) o jmxremote.ssl.enabled.cipher.suites: () com.sun.management . o jmxremote.ssl.enabled.cipher.suite: (STRING ) o jmxremote.ssl.enabled.protocols: () com.sun.management.jmxr emote.ssl.enabled.protocols (STRING ) o jmxremote.ssl.need.client.auth: () com.sun.management.jmxre mote.need.client.auth (STRING ) o jmxremote.ssl.config.file: () com.sun.management.jmxremote. ssl_config_file (STRING ) o jmxremote.autodiscovery: () com.sun.management.jmxremote.au todiscovery (STRING ) o jdp.port: () com.sun.management.jdp.port (INT ) o jdp.address: () com.sun.management.jdp.address (STRING ) o jdp.source_addr: () com.sun.management.jdp.source_addr (STRING ) o jdp.ttl: () com.sun.management.jdp.ttl (INT ) o jdp.pause: () com.sun.management.jdp.pause (INT ) o jdp.name: () com.sun.management.jdp.name (STRING ) ManagementAgent.start_local . : --- ManagementAgent.status . : --- ManagementAgent.stop . : --- System.dump_map [] ( ) . : : key key=value . : o -H: () (BOOLEAN false) o -F: () . %p PID JVM . (FILE "vm_memory_map_%p.txt") System.map [] ( ) VM . : : key key=value . : o -H: () (BOOLEAN false) System.native_heap_info ( ) (native heap) malloc_info(3) . "Error: " . : System.trim_native_heap ( ) C (C-heap) . : Thread.dump_to_file [] filepath (threads) (stack traces) JSON. : : . : key key=value . :.IP o 2 -overwrite: () (BOOLEAN false) o -format: () ("plain" "json") (STRING plain) : o filepath: . %p PID JVM . (FILE ) Thread.print [] (stacktrace) . : --- . : key key=value . : o -e: () (BOOLEAN false) o -l: () java.util.concurrent (BOOLEAN false) Thread.vthread_scheduler . : Thread.vthread_pollers / (I/O pollers) / . : VM.cds [] (dump) . : --- : o subcmd: static_dump dynamic_dump (STRING ) o filename: () . %p PID JVM . (FILE "java_pid%p_.jsa") dynamic_dump JVM JVM -XX:+RecordDynamicDumpInfo . VM.class_hierarchy [] [] . *ClassLoaderData ClassLoader (bootstrap) "null" . : --- . : key key=value . : o -i: () (interfaces) . (BOOLEAN false) o -s: () classname . . (BOOLEAN false) : o classname: () . . (STRING ) VM.classes [] : : . key key=value . : o -verbose: () . : F = finalize ( ) f = final W = C = @Contended R = S = (BOOLEAN false) VM.classloader_stats ClassLoader . : VM.classloaders [] classloader . : --- . key key=value . : o show-classes: () . (BOOLEAN false) o verbose: () . (BOOLEAN false) o fold: () . (BOOLEAN true) VM.command_line VM . : VM.dynlibs . : VM.events [] VM : --- . : : key key=value . o log: () . . (STRING ) o max: () ( ). . (INT 0) VM.flags [] VM . : : key key=value . : o -all: () VM (BOOLEAN false). VM.info JVM . : VM.log [] // (rotate ). : : : key key=value . o output: () (#) . (STRING ) o output_options: () . (STRING ) o what: () (tags) . (STRING ).IP o 2 decorators: () . 'none' . (STRING ) o disable: () () . (BOOLEAN ) o list: () . (BOOLEAN ) o rotate: () (rotate). (BOOLEAN ) VM.metaspace [options] metaspace . : --- . : options key key=value . options: o basic: () ( safepoint ). (BOOLEAN false) o show-loaders: () . (BOOLEAN false) o show-classes: () show-loaders . (BOOLEAN false) o by-chunktype: () (chunk type). (BOOLEAN false) o by-spacetype: () . (BOOLEAN false) o vslist: () (virtual space) . (BOOLEAN false) o chunkfreelist: () (ChunkManager) . (BOOLEAN false) o scale: () . : 1 KB MB GB ( ) "dynamic" . (STRING dynamic) VM.native_memory [options] (native memory) . : : options key key=value . options: o summary: () (runtime) (committed) . (BOOLEAN false) o detail: () >= 1K (callsite) . (BOOLEAN false) o baseline: () . (BOOLEAN false) o summary.diff: () . (BOOLEAN false) o detail.diff: () . (BOOLEAN false) o statistics: () (tracker) . (BOOLEAN false) o scale: () KB MB GB (STRING KB) VM.set_flag [arguments] . : arguments: o flag name: (STRING ) o string value: () (STRING ) VM.stringtable [options] (string table) (dump) . : --- Java . : options key key=value . options: o -verbose: () (BOOLEAN false) VM.symboltable [options] (symbol table) (dump) . : --- Java . : options key key=value . options: o -verbose: () (BOOLEAN false) VM.system_properties (system properties) . : VM.systemdictionary (bucket length) . : : options key key=value . options: o verbose: () (BOOLEAN false). VM.uptime [options] (uptime) . : : options key key=value . options: o -date: () (BOOLEAN false) VM.version JVM . : JDK 25.0.4.1 2026 JCMD(1)