JDK监控和故障处理工具-jstat[转自Oracle]
来源:互联网 发布:pop3的端口号 编辑:程序博客网 时间:2024/05/16 17:09
jstat - Java Virtual Machine Statistics Monitoring Tool
- Synopsis
- Description
- Virtual Machine Identifier
- Options
- General Options
- Output Options - Examples
- See Also
SYNOPSIS
jstat [ generalOption | outputOptions vmid [interval[s|ms] [count]] ]
generalOption
- A single general command-line option (-help, -options, or -version)
outputOptions
- One or more output options, consisting of a single statOption, plus any of the -t, -h, and -J options.
vmid
- Virtual machine identifier, a string indicating the target Java virtual machine (JVM). The general syntax is
[protocol:][//]lvmid[@hostname[:port]/servername]
The syntax of the vmid string largely corresponds to the syntax of a URI. The vmid can vary from a simple integer representing a local JVM to a more complex construction specifying a communications protocol, port number, and other implementation-specific values. See Virtual Machine Identifier for details. interval[s|ms]
- Sampling interval in the specified units, seconds (s) or milliseconds (ms). Default units are milliseconds. Must be a positive integer. If specified, jstat will produce its output at each interval.
count
- Number of samples to display. Default value is infinity; that is, jstat displays statistics until the target JVM terminates or the jstat command is terminated. Must be a positive integer.
DESCRIPTION
The jstat tool displays performance statistics for an instrumented HotSpot Java virtual machine (JVM). The target JVM is identified by its virtual machine identifier, or vmid option described below.
NOTE: This utility is unsupported and may not be available in future versions of the J2SE SDK. It is not currently available on Windows 98 and Windows ME platforms.
VIRTUAL MACHINE IDENTIFIER
The syntax of the vmid string largely corresponds to the syntax of a URI:
[protocol:][//]lvmid[@hostname][:port][/servername]
protocol
- The communications protocol. If the protocol is omitted and a hostname is not specified, the default protocol is a platform specific optimized local protocol. If the protocol is omitted and a hostname is specified, then the default protocol is rmi.
lvmid
- The local virtual machine identifier for the target JVM. The lvmid is a platform-specific value that uniquely identifies a JVM on a system. Thelvmid is the only required component of a virtual machine identifier. The lvmid is typically, but not necessarily, the operating system's process identifier for the target JVM process. You can use the jps command to determine the lvmid. Also, you can determine lvmid on Unix platforms with the ps command, and on Windows with the Windows Task Manager.
hostname
- A hostname or IP address indicating the target host. If hostname is omitted, then the target host is the local host.
port
- The default port for communicating with the remote server. If the hostname is omitted or the protocol specifies an optimized, local protocol, thenport is ignored. Otherwise, treatment of the port parameter is implementation specific. For the default rmi protocol, the port indicates the port number for the rmiregistry on the remote host. If port is omitted, and protocol indicates rmi, then the default rmiregistry port (1099) is used.
servername
- The treatment of this parameter depends on implementation. For the optimized local protocol, this field is ignored. For the rmi protocol, it represents the name of the RMI remote object on the remote host.
OPTIONS
The jstat command supports two types of options, general options and output options. General options cause jstat to display simple usage and version information. Output options determine the content and format of the statistical output.
NOTE: All options, and their functionality are subject to change or removal in future releases.
GENERAL OPTIONS
If you specify one of the general options, you cannot specify any other option or parameter.
- -help
- Display help message.
- -version
- Display version information.
- -options
- Display list of statistics options. See the Output Options section below.
OUTPUT OPTIONS
If you do not specify a general option, then you can specify output options. Output options determine the content and format of jstat's output, and consist of a single statOption, plus any of the other output options (-h, -t, and -J). The statOption must come first.
Output is formatted as a table, with columns are separated by spaces. A header row with titles describes the columns. Use the -h option to set the frequency at which the header is displayed. Column header names are generally consistent between the different options. In general, if two options provide a column with the same name, then the data source for the two columns are the same.
Use the -t 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 startup of the target JVM. 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.
Use the interval and count parameters to determine how frequently and how many times, respectively, jstat displays its output.
NOTE: You are advised not to write scripts to parse jstat's output since the format may change in future releases. If you choose to write scripts that parse jstat output, expect to modify them for future releases of this tool.
- -statOption
- Determines the statistics information that jstat displays. The following table lists the available options. Use the -options general option to display the list of options for a particular platform installation.
Option Displays... classStatistics on the behavior of the class loader.compilerStatistics of the behavior of the HotSpot Just-in-Time compiler.gcStatistics of the behavior of the garbage collected heap.gccapacityStatistics of the capacities of the generations and their corresponding spaces.gccauseSummary of garbage collection statistics (same as -gcutil), with the cause of the last and current (if applicable) garbage collection events.gcnewStatistics of the behavior of the new generation.gcnewcapacityStatistics of the sizes of the new generations and its corresponding spaces.gcoldStatistics of the behavior of the old and permanent generations.gcoldcapacityStatistics of the sizes of the old generation.gcpermcapacityStatistics of the sizes of the permanent generation.gcutilSummary of garbage collection statistics.printcompilationHotSpot compilation method statistics. - -h n
- Display a column header every n samples (output rows), where n is a positive integer. Default value is 0, which displays the column header above the first row of data.
- -t n
- Display a timestamp column as the first column of output. The timestamp is the the time since the start time of the target JVM.
- -JjavaOption
- Pass javaOption to the java application launcher. For example, -J-Xms48m sets the startup memory to 48 megabytes. For a complete list of options, see the following documents:
- java - the Java application launcher (Solaris)
- java - the Java application launcher (Linux)
- java - the Java application launcher (Windows)
STATOPTIONS AND OUTPUT
The following tables summarize the columns that jstat outputs for each statOption.
-class Option
-compiler Option
-gc Option
-gccapacity Option
-gccause Option
This option displays the same summary of garbage collection statistics as the -gcutil option, but includes the causes of the last garbage collection event and (if applicable) the current garbage collection event. In addition to the columns listed for -gcutil, this option adds the following columns:
-gcnew Option
-gcnewcapacity Option
-gcold Option
-gcoldcapacity Option
-gcpermcapacity Option
-gcutil Option
-printcompilation Option
EXAMPLES
This section presents some examples of monitoring a local JVM with a lvmid of 21891.
Using the gcutil option
This example attaches to lvmid 21891 and takes 7 samples at 250 millisecond intervals and displays the output as specified by the -gcutil option.
jstat -gcutil 21891 250 7 S0 S1 E O P YGC YGCT FGC FGCT GCT 12.44 0.00 27.20 9.49 96.70 78 0.176 5 0.495 0.672 12.44 0.00 62.16 9.49 96.70 78 0.176 5 0.495 0.672 12.44 0.00 83.97 9.49 96.70 78 0.176 5 0.495 0.672 0.00 7.74 0.00 9.51 96.70 79 0.177 5 0.495 0.673 0.00 7.74 23.37 9.51 96.70 79 0.177 5 0.495 0.673 0.00 7.74 43.82 9.51 96.70 79 0.177 5 0.495 0.673 0.00 7.74 58.11 9.51 96.71 79 0.177 5 0.495 0.673
The output of this example shows that a young generation collection occurred between the 3rd and 4th sample. The collection took 0.001 seconds and promoted objects from the eden space (E) to the old space (O), resulting in an increase of old space utilization from 9.49% to 9.51%. Before the collection, the survivor space was 12.44% utilized, but after this collection it is only 7.74% utilized.
Repeating the column header string
This example attaches to lvmid 21891 and takes samples at 250 millisecond intervals and displays the output as specified by -gcutil option. In addition, it uses the -h3 option to output the column header after every 3 lines of data.
jstat -gcnew -h3 21891 250 S0C S1C S0U S1U TT MTT DSS EC EU YGC YGCT 64.0 64.0 0.0 31.7 31 31 32.0 512.0 178.6 249 0.203 64.0 64.0 0.0 31.7 31 31 32.0 512.0 355.5 249 0.203 64.0 64.0 35.4 0.0 2 31 32.0 512.0 21.9 250 0.204 S0C S1C S0U S1U TT MTT DSS EC EU YGC YGCT 64.0 64.0 35.4 0.0 2 31 32.0 512.0 245.9 250 0.204 64.0 64.0 35.4 0.0 2 31 32.0 512.0 421.1 250 0.204 64.0 64.0 0.0 19.0 31 31 32.0 512.0 84.4 251 0.204 S0C S1C S0U S1U TT MTT DSS EC EU YGC YGCT 64.0 64.0 0.0 19.0 31 31 32.0 512.0 306.7 251 0.204
In addition to showing the repeating header string, this example shows that between the 2nd and 3rd samples, a young GC occurred. Its duration was 0.001 seconds. The collection found enough live data that the survivor space 0 utilization (S0U) would 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.
Another collection occurs between the 5th and 6th samples. This collection found very few survivors and returned the tenuring threshold to 31.
Including a time stamp for each sample
This example attaches to lvmid 21891 and takes 3 samples at 250 millisecond intervals. The -t option is used to generate a time stamp for each sample in the first column.
jstat -gcoldcapacity -t 21891 250 3Timestamp OGCMN OGCMX OGC OC YGC FGC FGCT GCT 150.1 1408.0 60544.0 11696.0 11696.0 194 80 2.874 3.799 150.4 1408.0 60544.0 13820.0 13820.0 194 81 2.938 3.863 150.7 1408.0 60544.0 13820.0 13820.0 194 81 2.938 3.863
The Timestamp
column reports the elapsed time in seconds since the start of the target JVM. In addition, the -gcoldcapacity output shows the old generation capacity (OGC) and the old space capacity (OC) increasing as the heap expands to meet allocation and/or promotion demands. The old generation capacity (OGC) has grown to from 11696 KB to 13820 KB after the 81st Full GC (FGC). The maximum capacity of the generation (and space) is 60544 KB (OGCMX), so it still has room to expand.
Monitor instrumentation for a remote JVM
This example attaches to lvmid 40496 on the system named remote.domain using the -gcutil option, with samples taken every second indefinitely.
jstat -gcutil 40496@remote.domain 1000... output omitted
The lvmid is combined with the name of the remote host to construct a vmid of 40496@remote.domain. This vmid results in the use of the rmi protocol to communicate to the default jstatd server on the remote host. The jstatd server is located using the rmiregistry on remote.domain that is bound to the default rmiregistry port (port 1099).
SEE ALSO
- java - the Java Application Launcher
- jps - the Java Process Status Application
- jstatd - the jvmstat daemon
- rmiregistry - the Java Remote Object Registry
Copyright © 2004, 2010 Oracle and/or its affiliates. All rights reserved.
- JDK监控和故障处理工具-jstat[转自Oracle]
- JDK监控和故障处理工具-jps[转自Oracle]
- JDK监控和故障处理工具-jinfo[转自Oracle]
- JDK监控和故障处理工具-jmap[转自Oracle]
- JVM (PART XII) Sun JDK 监控和故障处理工具(II)jstat
- Sun JDK监控和故障处理工具.
- JDK监控和故障处理工具
- Sun JDK 监控和故障处理工具
- JDK常用监控和故障处理工具
- jdk自带监控工具整理-jstat
- Sun JDK监控和故障处理工具:jps
- 常用的几款JDK监控和故障处理工具
- JVM虚拟机:JDK监控和故障处理工具
- JDK自带监控工具 jps、jinfo、jstat、jmap
- JDK自带监控工具 jps、jinfo、jstat、jmap、jconsole
- 虚拟机性能监控与故障处理工具-JDK命令行工具
- JVM性能监控和故障处理工具
- 虚拟机性能监控和故障处理工具
- vc++ 访问php webService
- java中使用oracle的绑定变量
- JDK监控和故障处理工具-jps[转自Oracle]
- Myeclipse JQuery自动提示
- 【转】ios 设置背景图片
- JDK监控和故障处理工具-jstat[转自Oracle]
- 调用getLoaderManager().initLoader()时出现ClassCastException的解决方式
- android ListView几个比较特别的属性
- MySQL导入导出数据库文件
- JDK监控和故障处理工具-jinfo[转自Oracle]
- [iOS]提交iPhone app程序遇到newsstand错误
- Oracle建立表空间和用户
- JDK监控和故障处理工具-jmap[转自Oracle]
- 在cmd里面运行adb命令的时候提示:adb server is out of date. killing...