src/linux/doc/man/jstat.1

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.\" Title: jstat
.\" Language: English
.\" Date: 03 March 2015
.\" SectDesc: Monitoring Tools
.\" Software: JDK 8
.\" Arch: generic
.\" Part Number: E38207-04
.\" Doc ID: JSSON
.\"
.if n .pl 99999
.TH "jstat" "1" "03 March 2015" "JDK 8" "Monitoring Tools"
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.SH "NAME"
jstat \- Monitors Java Virtual Machine (JVM) statistics\&. This command is experimental and unsupported\&.
.SH "SYNOPSIS"
.sp
.if n \{\
.RS 4
.\}
.nf
\fBjstat\fR [ \fIgeneralOption\fR | \fIoutputOptions vmid\fR [ \fIinterval\fR[s|ms] [ \fIcount \fR] ]
.fi
.if n \{\
.RE
.\}
.PP
\fIgeneralOption\fR
.RS 4
A single general command\-line option
\fB\-help\fR
or
\fB\-options\fR\&. See General Options\&.
.RE
.PP
\fIoutputOptions\fR
.RS 4
One or more output options that consist of a single
\fBstatOption\fR, plus any of the
\fB\-t\fR,
\fB\-h\fR, and
\fB\-J\fR
options\&. See Output Options\&.
.RE
.PP
\fIvmid\fR
.RS 4
Virtual machine identifier, which is a string that indicates the target JVM\&. The general syntax is the following:
.sp
.if n \{\
.RS 4
.\}
.nf
\fB[protocol:][//]lvmid[@hostname[:port]/servername]\fR
 
.fi
.if n \{\
.RE
.\}
The syntax of the
\fBvmid\fR
string corresponds to the syntax of a URI\&. The
\fBvmid\fR
string can vary from a simple integer that represents a local JVM to a more complex construction that specifies a communications protocol, port number, and other implementation\-specific values\&. See Virtual Machine Identifier\&.
.RE
.PP
\fIinterval\fR [s|ms]
.RS 4
Sampling interval in the specified units, seconds (s) or milliseconds (ms)\&. Default units are milliseconds\&. Must be a positive integer\&. When specified, the
\fBjstat\fR
command produces its output at each interval\&.
.RE
.PP
\fIcount\fR
.RS 4
Number of samples to display\&. The default value is infinity which causes the
\fBjstat\fR
command to display statistics until the target JVM terminates or the
\fBjstat\fR
command is terminated\&. This value must be a positive integer\&.
.RE
.SH "DESCRIPTION"
.PP
The
\fBjstat\fR
command displays performance statistics for an instrumented Java HotSpot VM\&. The target JVM is identified by its virtual machine identifier, or
\fBvmid\fR
option\&.
.SH "VIRTUAL MACHINE IDENTIFIER"
.PP
The syntax of the
\fBvmid\fR
string corresponds to the syntax of a URI:
.sp
.if n \{\
.RS 4
.\}
.nf
\fB[protocol:][//]lvmid[@hostname[:port]/servername]\fR
 
.fi
.if n \{\
.RE
.\}
.PP
\fIprotocol\fR
.RS 4
The communications protocol\&. If the
\fIprotocol\fR
value is omitted and a host name is not specified, then the default protocol is a platform\-specific optimized local protocol\&. If the
\fIprotocol\fR
value is omitted and a host name is specified, then the default protocol is
\fBrmi\fR\&.
.RE
.PP
\fIlvmid\fR
.RS 4
The local virtual machine identifier for the target JVM\&. The
\fBlvmid\fR
is a platform\-specific value that uniquely identifies a JVM on a system\&. The
\fBlvmid\fR
is the only required component of a virtual machine identifier\&. The
\fBlvmid\fR
is typically, but not necessarily, the operating system\*(Aqs process identifier for the target JVM process\&. You can use the
\fBjps\fR
command to determine the
\fBlvmid\fR\&. Also, you can determine the
\fBlvmid\fR
on Solaris, Linux, and OS X platforms with the
\fBps\fR
command, and on Windows with the Windows Task Manager\&.
.RE
.PP
\fIhostname\fR
.RS 4
A hostname or IP address that indicates the target host\&. If the
\fIhostname\fR
value is omitted, then the target host is the local host\&.
.RE
.PP
\fIport\fR
.RS 4
The default port for communicating with the remote server\&. If the
\fIhostname\fR
value is omitted or the
\fIprotocol\fR
value specifies an optimized, local protocol, then the
\fIport\fR
value is ignored\&. Otherwise, treatment of the
\fBport\fR
parameter is implementation\-specific\&. For the default
\fBrmi\fR
protocol, the port value indicates the port number for the rmiregistry on the remote host\&. If the
\fIport\fR
value is omitted and the
\fIprotocol\fR
value indicates
\fBrmi\fR, then the default rmiregistry port (1099) is used\&.
.RE
.PP
\fIservername\fR
.RS 4
The treatment of the
\fBservername\fR
parameter depends on implementation\&. For the optimized local protocol, this field is ignored\&. For the
\fBrmi\fR
protocol, it represents the name of the RMI remote object on the remote host\&.
.RE
.SH "OPTIONS"
.PP
The
\fBjstat\fR
command supports two types of options, general options and output options\&. General options cause the
\fBjstat\fR
command to display simple usage and version information\&. Output options determine the content and format of the statistical output\&.
.PP
All options and their functionality are subject to change or removal in future releases\&.
.SS "General Options"
.PP
If you specify one of the general options, then you cannot specify any other option or parameter\&.
.PP
\-help
.RS 4
Displays a help message\&.
.RE
.PP
\-options
.RS 4
Displays a list of static options\&. See Output Options\&.
.RE
.SS "Output Options"
.PP
If you do not specify a general option, then you can specify output options\&. Output options determine the content and format of the
\fBjstat\fR
command\*(Aqs output, and consist of a single
\fBstatOption\fR, plus any of the other output options (\fB\-h\fR,
\fB\-t\fR, and
\fB\-J\fR)\&. The
\fBstatOption\fR
must come first\&.
.PP
Output is formatted as a table, with columns that are separated by spaces\&. A header row with titles describes the columns\&. Use the
\fB\-h\fR
option to set the frequency at which the header is displayed\&. Column header names are consistent among the different options\&. In general, if two options provide a column with the same name, then the data source for the two columns is the same\&.
.PP
Use the
\fB\-t\fR
option to display a time stamp column, labeled Timestamp as the first column of output\&. The Timestamp column contains the elapsed time, in seconds, since the target JVM started\&. The resolution of the time stamp is dependent on various factors and is subject to variation due to delayed thread scheduling on heavily loaded systems\&.
.PP
Use the interval and count parameters to determine how frequently and how many times, respectively, the
\fBjstat\fR
command displays its output\&.
.PP
\fBNote:\fR
Do not to write scripts to parse the
\fBjstat\fR
command\*(Aqs output because the format might change in future releases\&. If you write scripts that parse
\fBjstat\fR
command output, then expect to modify them for future releases of this tool\&.
.PP
\-\fIstatOption\fR
.RS 4
Determines the statistics information the
\fBjstat\fR
command displays\&. The following lists the available options\&. Use the
\fB\-options\fR
general option to display the list of options for a particular platform installation\&. See Stat Options and Output\&.
.sp
\fBclass\fR: Displays statistics about the behavior of the class loader\&.
.sp
\fBcompiler\fR: Displays statistics about the behavior of the Java HotSpot VM Just\-in\-Time compiler\&.
.sp
\fBgc\fR: Displays statistics about the behavior of the garbage collected heap\&.
.sp
\fBgccapacity\fR: Displays statistics about the capacities of the generations and their corresponding spaces\&.
.sp
\fBgccause\fR: Displays a summary about garbage collection statistics (same as
\fB\-gcutil\fR), with the cause of the last and current (when applicable) garbage collection events\&.
.sp
\fBgcnew\fR: Displays statistics of the behavior of the new generation\&.
.sp
\fBgcnewcapacity\fR: Displays statistics about the sizes of the new generations and its corresponding spaces\&.
.sp
\fBgcold\fR: Displays statistics about the behavior of the old generation and metaspace statistics\&.
.sp
\fBgcoldcapacity\fR: Displays statistics about the sizes of the old generation\&.
.sp
\fBgcmetacapacity\fR: Displays statistics about the sizes of the metaspace\&.
.sp
\fBgcutil\fR: Displays a summary about garbage collection statistics\&.
.sp
\fBprintcompilation\fR: Displays Java HotSpot VM compilation method statistics\&.
.RE
.PP
\-h \fIn\fR
.RS 4
Displays a column header every
\fIn\fR
samples (output rows), where
\fIn\fR
is a positive integer\&. Default value is 0, which displays the column header the first row of data\&.
.RE
.PP
\-t
.RS 4
Displays a timestamp column as the first column of output\&. The time stamp is the time since the start time of the target JVM\&.
.RE
.PP
\-J\fIjavaOption\fR
.RS 4
Passes
\fBjavaOption\fR
to the Java application launcher\&. For example,
\fB\-J\-Xms48m\fR
sets the startup memory to 48 MB\&. For a complete list of options, see
java(1)\&.
.RE
.SS "Stat Options and Output"
.PP
The following information summarizes the columns that the
\fBjstat\fR
command outputs for each
\fIstatOption\fR\&.
.PP
\-class \fIoption\fR
.RS 4
Class loader statistics\&.
.sp
\fBLoaded\fR: Number of classes loaded\&.
.sp
\fBBytes\fR: Number of kBs loaded\&.
.sp
\fBUnloaded\fR: Number of classes unloaded\&.
.sp
\fBBytes\fR: Number of Kbytes unloaded\&.
.sp
\fBTime\fR: Time spent performing class loading and unloading operations\&.
.RE
.PP
\-compiler \fIoption\fR
.RS 4
Java HotSpot VM Just\-in\-Time compiler statistics\&.
.sp
\fBCompiled\fR: Number of compilation tasks performed\&.
.sp
\fBFailed\fR: Number of compilations tasks failed\&.
.sp
\fBInvalid\fR: Number of compilation tasks that were invalidated\&.
.sp
\fBTime\fR: Time spent performing compilation tasks\&.
.sp
\fBFailedType\fR: Compile type of the last failed compilation\&.
.sp
\fBFailedMethod\fR: Class name and method of the last failed compilation\&.
.RE
.PP
\-gc \fIoption\fR
.RS 4
Garbage\-collected heap statistics\&.
.sp
\fBS0C\fR: Current survivor space 0 capacity (kB)\&.
.sp
\fBS1C\fR: Current survivor space 1 capacity (kB)\&.
.sp
\fBS0U\fR: Survivor space 0 utilization (kB)\&.
.sp
\fBS1U\fR: Survivor space 1 utilization (kB)\&.
.sp
\fBEC\fR: Current eden space capacity (kB)\&.
.sp
\fBEU\fR: Eden space utilization (kB)\&.
.sp
\fBOC\fR: Current old space capacity (kB)\&.
.sp
\fBOU\fR: Old space utilization (kB)\&.
.sp
\fBMC\fR: Metaspace capacity (kB)\&.
.sp
\fBMU\fR: Metacspace utilization (kB)\&.
.sp
\fBCCSC\fR: Compressed class space capacity (kB)\&.
.sp
\fBCCSU\fR: Compressed class space used (kB)\&.
.sp
\fBYGC\fR: Number of young generation garbage collection events\&.
.sp
\fBYGCT\fR: Young generation garbage collection time\&.
.sp
\fBFGC\fR: Number of full GC events\&.
.sp
\fBFGCT\fR: Full garbage collection time\&.
.sp
\fBGCT\fR: Total garbage collection time\&.
.RE
.PP
\-gccapacity \fIoption\fR
.RS 4
Memory pool generation and space capacities\&.
.sp
\fBNGCMN\fR: Minimum new generation capacity (kB)\&.
.sp
\fBNGCMX\fR: Maximum new generation capacity (kB)\&.
.sp
\fBNGC\fR: Current new generation capacity (kB)\&.
.sp
\fBS0C\fR: Current survivor space 0 capacity (kB)\&.
.sp
\fBS1C\fR: Current survivor space 1 capacity (kB)\&.
.sp
\fBEC\fR: Current eden space capacity (kB)\&.
.sp
\fBOGCMN\fR: Minimum old generation capacity (kB)\&.
.sp
\fBOGCMX\fR: Maximum old generation capacity (kB)\&.
.sp
\fBOGC\fR: Current old generation capacity (kB)\&.
.sp
\fBOC\fR: Current old space capacity (kB)\&.
.sp
\fBMCMN\fR: Minimum metaspace capacity (kB)\&.
.sp
\fBMCMX\fR: Maximum metaspace capacity (kB)\&.
.sp
\fBMC\fR: Metaspace capacity (kB)\&.
.sp
\fBCCSMN\fR: Compressed class space minimum capacity (kB)\&.
.sp
\fBCCSMX\fR: Compressed class space maximum capacity (kB)\&.
.sp
\fBCCSC\fR: Compressed class space capacity (kB)\&.
.sp
\fBYGC\fR: Number of young generation GC events\&.
.sp
\fBFGC\fR: Number of full GC events\&.
.RE
.PP
\-gccause \fIoption\fR
.RS 4
This option displays the same summary of garbage collection statistics as the
\fB\-gcutil\fR
option, but includes the causes of the last garbage collection event and (when applicable) the current garbage collection event\&. In addition to the columns listed for
\fB\-gcutil\fR, this option adds the following columns\&.
.sp
\fBLGCC\fR: Cause of last garbage collection
.sp
\fBGCC\fR: Cause of current garbage collection
.RE
.PP
\-gcnew \fIoption\fR
.RS 4
New generation statistics\&.
.sp
\fBS0C\fR: Current survivor space 0 capacity (kB)\&.
.sp
\fBS1C\fR: Current survivor space 1 capacity (kB)\&.
.sp
\fBS0U\fR: Survivor space 0 utilization (kB)\&.
.sp
\fBS1U\fR: Survivor space 1 utilization (kB)\&.
.sp
\fBTT\fR: Tenuring threshold\&.
.sp
\fBMTT\fR: Maximum tenuring threshold\&.
.sp
\fBDSS\fR: Desired survivor size (kB)\&.
.sp
\fBEC\fR: Current eden space capacity (kB)\&.
.sp
\fBEU\fR: Eden space utilization (kB)\&.
.sp
\fBYGC\fR: Number of young generation GC events\&.
.sp
\fBYGCT\fR: Young generation garbage collection time\&.
.RE
.PP
\-gcnewcapacity \fIoption\fR
.RS 4
New generation space size statistics\&.
.sp
\fBNGCMN\fR: Minimum new generation capacity (kB)\&.
.sp
\fBNGCMX\fR: Maximum new generation capacity (kB)\&.
.sp
\fBNGC\fR: Current new generation capacity (kB)\&.
.sp
\fBS0CMX\fR: Maximum survivor space 0 capacity (kB)\&.
.sp
\fBS0C\fR: Current survivor space 0 capacity (kB)\&.
.sp
\fBS1CMX\fR: Maximum survivor space 1 capacity (kB)\&.
.sp
\fBS1C\fR: Current survivor space 1 capacity (kB)\&.
.sp
\fBECMX\fR: Maximum eden space capacity (kB)\&.
.sp
\fBEC\fR: Current eden space capacity (kB)\&.
.sp
\fBYGC\fR: Number of young generation GC events\&.
.sp
\fBFGC\fR: Number of full GC events\&.
.RE
.PP
\-gcold \fIoption\fR
.RS 4
Old generation and metaspace behavior statistics\&.
.sp
\fBMC\fR: Metaspace capacity (kB)\&.
.sp
\fBMU\fR: Metaspace utilization (kB)\&.
.sp
\fBCCSC\fR: Compressed class space capacity (kB)\&.
.sp
\fBCCSU\fR: Compressed class space used (kB)\&.
.sp
\fBOC\fR: Current old space capacity (kB)\&.
.sp
\fBOU\fR: Old space utilization (kB)\&.
.sp
\fBYGC\fR: Number of young generation GC events\&.
.sp
\fBFGC\fR: Number of full GC events\&.
.sp
\fBFGCT\fR: Full garbage collection time\&.
.sp
\fBGCT\fR: Total garbage collection time\&.
.RE
.PP
\-gcoldcapacity \fIoption\fR
.RS 4
Old generation size statistics\&.
.sp
\fBOGCMN\fR: Minimum old generation capacity (kB)\&.
.sp
\fBOGCMX\fR: Maximum old generation capacity (kB)\&.
.sp
\fBOGC\fR: Current old generation capacity (kB)\&.
.sp
\fBOC\fR: Current old space capacity (kB)\&.
.sp
\fBYGC\fR: Number of young generation GC events\&.
.sp
\fBFGC\fR: Number of full GC events\&.
.sp
\fBFGCT\fR: Full garbage collection time\&.
.sp
\fBGCT\fR: Total garbage collection time\&.
.RE
.PP
\-gcmetacapacity \fIoption\fR
.RS 4
Metaspace size statistics\&.
.sp
\fBMCMN\fR: Minimum metaspace capacity (kB)\&.
.sp
\fBMCMX\fR: Maximum metaspace capacity (kB)\&.
.sp
\fBMC\fR: Metaspace capacity (kB)\&.
.sp
\fBCCSMN\fR: Compressed class space minimum capacity (kB)\&.
.sp
\fBCCSMX\fR: Compressed class space maximum capacity (kB)\&.
.sp
\fBYGC\fR: Number of young generation GC events\&.
.sp
\fBFGC\fR: Number of full GC events\&.
.sp
\fBFGCT\fR: Full garbage collection time\&.
.sp
\fBGCT\fR: Total garbage collection time\&.
.RE
.PP
\-gcutil \fIoption\fR
.RS 4
Summary of garbage collection statistics\&.
.sp
\fBS0\fR: Survivor space 0 utilization as a percentage of the space\*(Aqs current capacity\&.
.sp
\fBS1\fR: Survivor space 1 utilization as a percentage of the space\*(Aqs current capacity\&.
.sp
\fBE\fR: Eden space utilization as a percentage of the space\*(Aqs current capacity\&.
.sp
\fBO\fR: Old space utilization as a percentage of the space\*(Aqs current capacity\&.
.sp
\fBM\fR: Metaspace utilization as a percentage of the space\*(Aqs current capacity\&.
.sp
\fBCCS\fR: Compressed class space utilization as a percentage\&.
.sp
\fBYGC\fR: Number of young generation GC events\&.
.sp
\fBYGCT\fR: Young generation garbage collection time\&.
.sp
\fBFGC\fR: Number of full GC events\&.
.sp
\fBFGCT\fR: Full garbage collection time\&.
.sp
\fBGCT\fR: Total garbage collection time\&.
.RE
.PP
\-printcompilation \fIoption\fR
.RS 4
Java HotSpot VM compiler method statistics\&.
.sp
\fBCompiled\fR: Number of compilation tasks performed by the most recently compiled method\&.
.sp
\fBSize\fR: Number of bytes of byte code of the most recently compiled method\&.
.sp
\fBType\fR: Compilation type of the most recently compiled method\&.
.sp
\fBMethod\fR: Class name and method name identifying the most recently compiled method\&. Class name uses slash (/) instead of dot (\&.) as a name space separator\&. Method name is the method within the specified class\&. The format for these two fields is consistent with the HotSpot
\fB\-XX:+PrintCompilation\fR
option\&.
.RE
.SH "EXAMPLES"
.PP
This section presents some examples of monitoring a local JVM with an
\fIlvmid\fR
of 21891\&.
.SS "The gcutil Option"
.PP
This example attaches to lvmid 21891 and takes 7 samples at 250 millisecond intervals and displays the output as specified by the \-\fBgcutil\fR
option\&.
.PP
The output of this example shows that a young generation collection occurred between the third and fourth sample\&. The collection took 0\&.078 seconds and promoted objects from the eden space (E) to the old space (O), resulting in an increase of old space utilization from 66\&.80% to 68\&.19%\&. Before the collection, the survivor space was 97\&.02% utilized, but after this collection it is 91\&.03% utilized\&.
.sp
.if n \{\
.RS 4
.\}
.nf
\fBjstat \-gcutil 21891 250 7\fR
\fB  S0     S1     E      O      M     CCS    YGC     YGCT    FGC    FGCT     GCT   \fR
\fB  0\&.00  97\&.02  70\&.31  66\&.80  95\&.52  89\&.14      7    0\&.300     0    0\&.000    0\&.300\fR
\fB  0\&.00  97\&.02  86\&.23  66\&.80  95\&.52  89\&.14      7    0\&.300     0    0\&.000    0\&.300\fR
\fB  0\&.00  97\&.02  96\&.53  66\&.80  95\&.52  89\&.14      7    0\&.300     0    0\&.000    0\&.300\fR
\fB 91\&.03   0\&.00   1\&.98  68\&.19  95\&.89  91\&.24      8    0\&.378     0    0\&.000    0\&.378\fR
\fB 91\&.03   0\&.00  15\&.82  68\&.19  95\&.89  91\&.24      8    0\&.378     0    0\&.000    0\&.378\fR
\fB 91\&.03   0\&.00  17\&.80  68\&.19  95\&.89  91\&.24      8    0\&.378     0    0\&.000    0\&.378\fR
\fB 91\&.03   0\&.00  17\&.80  68\&.19  95\&.89  91\&.24      8    0\&.378     0    0\&.000    0\&.378\fR
.fi
.if n \{\
.RE
.\}
.SS "Repeat the Column Header String"
.PP
This example attaches to lvmid 21891 and takes samples at 250 millisecond intervals and displays the output as specified by
\fB\-gcnew\fR
option\&. In addition, it uses the
\fB\-h3\fR
option to output the column header after every 3 lines of data\&.
.PP
In addition to showing the repeating header string, this example shows that between the second and third samples, a young GC occurred\&. Its duration was 0\&.001 seconds\&. The collection found enough active data that the survivor space 0 utilization (S0U) would have exceeded the desired survivor Size (DSS)\&. As a result, objects were promoted to the old generation (not visible in this output), and the tenuring threshold (TT) was lowered from 31 to 2\&.
.PP
Another collection occurs between the fifth and sixth samples\&. This collection found very few survivors and returned the tenuring threshold to 31\&.
.sp
.if n \{\
.RS 4
.\}
.nf
\fBjstat \-gcnew \-h3 21891 250\fR
\fB S0C    S1C    S0U    S1U   TT MTT  DSS      EC       EU     YGC     YGCT\fR
\fB  64\&.0   64\&.0    0\&.0   31\&.7 31  31   32\&.0    512\&.0    178\&.6    249    0\&.203\fR
\fB  64\&.0   64\&.0    0\&.0   31\&.7 31  31   32\&.0    512\&.0    355\&.5    249    0\&.203\fR
\fB  64\&.0   64\&.0   35\&.4    0\&.0  2  31   32\&.0    512\&.0     21\&.9    250    0\&.204\fR
\fB S0C    S1C    S0U    S1U   TT MTT  DSS      EC       EU     YGC     YGCT\fR
\fB  64\&.0   64\&.0   35\&.4    0\&.0  2  31   32\&.0    512\&.0    245\&.9    250    0\&.204\fR
\fB  64\&.0   64\&.0   35\&.4    0\&.0  2  31   32\&.0    512\&.0    421\&.1    250    0\&.204\fR
\fB  64\&.0   64\&.0    0\&.0   19\&.0 31  31   32\&.0    512\&.0     84\&.4    251    0\&.204\fR
\fB S0C    S1C    S0U    S1U   TT MTT  DSS      EC       EU     YGC     YGCT\fR
\fB  64\&.0   64\&.0    0\&.0   19\&.0 31  31   32\&.0    512\&.0    306\&.7    251    0\&.204\fR
 
.fi
.if n \{\
.RE
.\}
.SS "Include a Time Stamp for Each Sample"
.PP
This example attaches to lvmid 21891 and takes 3 samples at 250 millisecond intervals\&. The
\fB\-t\fR
option is used to generate a time stamp for each sample in the first column\&.
.PP
The Timestamp column reports the elapsed time in seconds since the start of the target JVM\&. In addition, the
\fB\-gcoldcapacity\fR
output shows the old generation capacity (OGC) and the old space capacity (OC) increasing as the heap expands to meet allocation or promotion demands\&. The old generation capacity (OGC) has grown from 11,696 kB to 13,820 kB after the eighty\-first full garbage collection (FGC)\&. The maximum capacity of the generation (and space) is 60,544 kB (OGCMX), so it still has room to expand\&.
.sp
.if n \{\
.RS 4
.\}
.nf
\fBTimestamp      OGCMN    OGCMX     OGC       OC       YGC   FGC    FGCT    GCT\fR
\fB          150\&.1   1408\&.0  60544\&.0  11696\&.0  11696\&.0   194    80    2\&.874   3\&.799\fR
\fB          150\&.4   1408\&.0  60544\&.0  13820\&.0  13820\&.0   194    81    2\&.938   3\&.863\fR
\fB          150\&.7   1408\&.0  60544\&.0  13820\&.0  13820\&.0   194    81    2\&.938   3\&.863\fR
 
.fi
.if n \{\
.RE
.\}
.SS "Monitor Instrumentation for a Remote JVM"
.PP
This example attaches to lvmid 40496 on the system named remote\&.domain using the
\fB\-gcutil\fR
option, with samples taken every second indefinitely\&.
.PP
The lvmid is combined with the name of the remote host to construct a
\fIvmid\fR
of
\fB40496@remote\&.domain\fR\&. This vmid results in the use of the
\fBrmi\fR
protocol to communicate to the default
\fBjstatd\fR
server on the remote host\&. The
\fBjstatd\fR
server is located using the
\fBrmiregistry\fR
command on
\fBremote\&.domain\fR
that is bound to the default port of the
\fBrmiregistry\fR
command (port 1099)\&.
.sp
.if n \{\
.RS 4
.\}
.nf
\fBjstat \-gcutil 40496@remote\&.domain 1000\fR
\fB\fI\&.\&.\&. output omitted\fR\fR
 
.fi
.if n \{\
.RE
.\}
.SH "SEE ALSO"
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
java(1)
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
jps(1)
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
jstatd(1)
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
rmiregistry(1)
.RE
.br
'pl 8.5i
'bp