1JHSDB(1) JDK Commands JHSDB(1)
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6 jhsdb - attach to a Java process or launch a postmortem debugger to an‐
7 alyze the content of a core dump from a crashed Java Virtual Machine
8 (JVM)
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11 jhsdb clhsdb [--pid pid | --exe executable --core coredump]
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13 jhsdb hsdb [--pid pid | --exe executable --core coredump]
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15 jhsdb debugd (--pid pid | --exe executable --core coredump) [options]
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17 jhsdb jstack (--pid pid | --exe executable --core coredump | --connect
18 [server-id@]debugd-host) [options]
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20 jhsdb jmap (--pid pid | --exe executable --core coredump | --connect
21 [server-id@]debugd-host) [options]
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23 jhsdb jinfo (--pid pid | --exe executable --core coredump | --connect
24 [server-id@]debugd-host) [options]
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26 jhsdb jsnap (--pid pid | --exe executable --core coredump | --connect
27 [server-id@]debugd-host) [options]
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29 pid The process ID to which the jhsdb tool should attach. The
30 process must be a Java process. To get a list of Java processes
31 running on a machine, use the ps command or, if the JVM process‐
32 es are not running in a separate docker instance, the jps com‐
33 mand.
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35 executable
36 The Java executable file from which the core dump was produced.
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38 coredump
39 The core file to which the jhsdb tool should attach.
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41 [server-id@]debugd-host
42 An optional server ID and the address of the remote debug server
43 (debugd).
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45 options
46 The command-line options for a jhsdb mode. See Options for the
47 debugd Mode, Options for the jstack Mode, Options for the jmap
48 Mode, Options for the jinfo Mode, and Options for the jsnap
49 Mode.
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51 Note:
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53 Either the pid or the pair of executable and core files or the [server-
54 id@]debugd-host must be provided for debugd, jstack, jmap, jinfo and
55 jsnap modes.
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58 You can use the jhsdb tool to attach to a Java process or to launch a
59 postmortem debugger to analyze the content of a core-dump from a
60 crashed Java Virtual Machine (JVM). This command is experimental and
61 unsupported.
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63 Note:
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65 Attaching the jhsdb tool to a live process will cause the process to
66 hang and the process will probably crash when the debugger detaches.
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68 The jhsdb tool can be launched in any one of the following modes:
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70 jhsdb clhsdb
71 Starts the interactive command-line debugger.
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73 jhsdb hsdb
74 Starts the interactive GUI debugger.
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76 jhsdb debugd
77 Starts the remote debug server.
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79 jhsdb jstack
80 Prints stack and locks information.
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82 jhsdb jmap
83 Prints heap information.
84
85 jhsdb jinfo
86 Prints basic JVM information.
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88 jhsdb jsnap
89 Prints performance counter information.
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91 jhsdb command --help
92 Displays the options available for the command.
93
95 --serverid server-id
96 An optional unique ID for this debug server. This is required
97 if multiple debug servers are run on the same machine.
98
99 --rmiport port
100 Sets the port number to which the RMI connector is bound. If
101 not specified a random available port is used.
102
103 --registryport port
104 Sets the RMI registry port. This option overrides the system
105 property 'sun.jvm.hotspot.rmi.port'. If not specified, the sys‐
106 tem property is used. If the system property is not set, the
107 default port 1099 is used.
108
109 --hostname hostname
110 Sets the hostname the RMI connector is bound. The value could
111 be a hostname or an IPv4/IPv6 address. This option overrides
112 the system property 'java.rmi.server.hostname'. If not speci‐
113 fied, the system property is used. If the system property is
114 not set, a system hostname is used.
115
117 --flags
118 Prints the VM flags.
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120 --sysprops
121 Prints the Java system properties.
122
123 no option
124 Prints the VM flags and the Java system properties.
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127 no option
128 Prints the same information as Solaris pmap.
129
130 --heap Prints the java heap summary.
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132 --binaryheap
133 Dumps the java heap in hprof binary format.
134
135 --dumpfile name
136 The name of the dumpfile.
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138 --histo
139 Prints the histogram of java object heap.
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141 --clstats
142 Prints the class loader statistics.
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144 --finalizerinfo
145 Prints the information on objects awaiting finalization.
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148 --locks
149 Prints the java.util.concurrent locks information.
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151 --mixed
152 Attempts to print both java and native frames if the platform
153 allows it.
154
156 --all Prints all performance counters.
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160JDK 21 2023 JHSDB(1)