Apache JMeter is a 100% pure Java desktop application designed to load test client/server software (such as a web application ). It may be used to test performance both on static and dynamic resources such as static files, Java Servlets, CGI scripts, Java objects, databases , FTP servers , and more. JMeter can be used to simulate a heavy load on a server, network or object to test its strength or to analyze overall performance under different load types.

Additionally, JMeter can help you regression test your application by letting you create test scripts with assertions to validate that your application is returning the results you expect. For maximum flexibility, JMeter lets you create these assertions using regular expressions.

But please note that JMeter is not a browser.

1.1 History

Stefano Mazzocchi of the Apache Software Foundation was the original developer of JMeter. He wrote it primarily to test the performance of Apache JServ (a project that has since been replaced by the Apache Tomcat project). We redesigned JMeter to enhance the GUI and to add functional-testing capabilities.

1.2 The Future

We hope to see JMeter's capabilities rapidly expand as developers take advantage of its pluggable architecture. The primary goal of further development is to make JMeter the most useful regression testing tool as possible, without compromising JMeter's load-testing capabilities.

2. Getting Started

The easiest way to begin using JMeter is to first download the latest production release and install it. The release contains all of the files you need to build and run most types of tests, e.g. Web (HTTP/HTTPS), FTP, JDBC, LDAP, Java, and JUnit.

If you want to perform JDBC testing, then you will, of course, need the appropriate JDBC driver from your vendor. JMeter does not come with any JDBC drivers.

Other software that you may need to download:

• BeanShell - needed for the BeanShell

function and test elements • Java Activation Framework - needed for JavaMail • Java Mail - needed for Mail Visualiser, Mail Reader and WebService(SOAP) sampler • JMS - for JMS samplers • General Java download page

See the JMeter Classpath section for details on installing additional jars.

Next, start JMeter and go through the Building a Test Plan section of the User Guide to familiarize yourself with JMeter basics (for example, adding and removing elements).

Finally, go through the appropriate section on how to build a specific type of Test Plan. For example, if you are interested in testing a Web application, then see the section Building a Web Test Plan . The other specific Test Plan sections are:

• Advanced Web Test Plan • JDBC • FTP • JMS Point-to-Point • JMS Topic • LDAP • LDAP Extended • WebServices (SOAP) •

Once you are comfortable with building and running JMeter Test Plans, you can look into the various configuration elements (timers, listeners, assertions, and others) which give you more control over your Test Plans.

2.1 Requirements

JMeter requires your computing environment meets some minimum requirements.

2.1.1 Java Version

JMeter requires a fully compliant JVM 1.4 or higher.

Version 2.2 and later no longer support Java 1.3.

Because JMeter uses only standard Java APIs, please do not file bug reports if your JRE fails to run JMeter because of JRE implementation issues.

2.1.2 Operating Systems

JMeter is a 100% Java application and should run correctly on any system that has a compliant Java implementation. JMeter has been tested and works under:

• Unix (Solaris, Linux, etc) • Windows (98, NT, XP, etc)

• OpenVMS Alpha 7.3+

2.2 Optional

If you plan on doing JMeter development or want to use Sun's Java Standard Extension packages, then you will need one or more optional packages listed below.

2.2.1 Java Compiler

If you want to build the JMeter source or develop JMeter plugins, then you will need a fully compliant JDK 1.4 or higher.

2.2.2 SAX XML Parser

JMeter comes with Apache's Xerces XML parser . You have the option of telling JMeter to use a different XML parser. To do so, include the classes for the third-party parser in JMeter's classpath , and update the jmeter.properties file with the full classname of the parser implementation.

2.2.3 Email Support

JMeter has limited Email capabilities. It can send email based on test results, and has a POP/IMAP sampler. It does not currently support SMTP sampling. To enable Email support, add Sun's JavaMail packages and the activation packages to JMeter's classpath .

2.2.4 SSL Encryption

To test a web server using SSL encryption (HTTPS), JMeter requires that an implementation of SSL be provided, as is the case with Sun Java 1.4 and above. If your version of Java does not include SSL support, then it is possible to add an external implementation. Include the necessary encryption packages in JMeter's classpath . Also, update system.properties to register the SSL Provider.

JMeter defaults to protocol level TLS. This can be changed by editting the JMeter property "https.default.protocol" in jmeter.properties or user.properties.

JMeter is configured to accept all certificates, whether trusted or not, regardless of validity periods etc. This is to allow the maximum flexibility in testing servers.

If the server requires a client certificate, this can be provided.

There is also the SSL Manager , for greater control of certificates.

The JMeter proxy server (see below) does not support recording SSL (https).

2.2.5 JDBC Driver

You will need to add your database vendor's JDBC driver to the classpath if you want to do JDBC testing. Make sure the file is a jar file, not a zip.

2.2.6 Apache SOAP

Apache SOAP requires mail.jar and activation.jar. You need to download and copy these two jar files to your jmeter/lib directory. Once the files are in there, JMeter will automatically pick them up.

2.2.7 BeanShell

To run the BeanShell function or any of the BeanShell test elements (sampler, timer etc), you need to download the beanshell jar from http://www.beanshell.org/ and copy the jar file to the jmeter/lib directory , where JMeter will automatically pick it up.

2.2.7 Libraries for ActiveMQ 3.0

See http://activemq.apache.org/initial-configuration.html for details.

See the JMeter Classpath section for more details on installing additional jars.

2.3 Installation

Note: avoid installing JMeter in a path with spaces in the name. This causes problems for remote testing.

We recommend that most users run the latest release .

To install a release build, simply unzip the zip/tar file into the directory where you want JMeter to be installed. Provided that you have a JRE/JDK correctly installed and the JAVA_HOME environment variable set, there is nothing more for you to do.

The installation directory structure should look something like this (for version 2.3.1):

jakarta-jmeter-2.3.1jakarta-jmeter-2.3.1/binjakarta-jmeter-2.3.1/docsjakarta-jmeter-2.3.1/extrasjakarta-jmeter-2.3.1/lib/jakarta-jmeter-2.3.1/lib/extjakarta-jmeter-2.3.1/lib/junitjakarta-jmeter-2.3.1/printable_docs

You can rename the parent directory (e.g. jakarta-jmeter-2.3.1) if you want, but do not change any of the sub-directory names. The path to the parent directory should not contain any spaces; if it does, then you may have problems running client-server mode.

2.4 Running JMeter

To run JMeter, run the jmeter.bat (for Windows) or jmeter (for Unix) file. These files are found in the bin directory. After a short pause, the JMeter GUI should appear.

There are some additional scripts in the bin directory that you may find useful. Windows script files (the .CMD files require Win2K or later):

• jmeter.bat - run JMeter (in GUI mode by default) • jmeter-n.cmd - drop a JMX file on this to run a non-GUI test • jmeter-n-r.cmd - drop a JMX file on this to run a non-GUI test remotely • jmeter-t.cmd - drop a JMX file on this to load it in GUI mode • jmeter-server.bat - start JMeter in server mode

Note: the special name LAST can be used with jmeter-n.cmd, jmeter-t.cmd and jmeter-n-r.cmd and means the last test plan that was run interactively.

Un*x script files; should work on most Linux/Unix systems.

• jmeter - run JMeter (in GUI mode by default) • jmeter-server - start JMeter in server mode

2.4.1 JMeter's Classpath

JMeter automatically finds classes from jars in the following directories:

• JMETER_HOME/lib - used for utility jars • JMETER_HOME/lib/ext - used for JMeter components and add-ons

If you have developed new JMeter components, then you should jar them and copy the jar into JMeter's lib/ext directory. JMeter will automatically find JMeter components in any jars found here.

Support jars (libraries etc) should be placed in the lib directory.

If you don't want to put the extension jars in the lib/ext directory, then define the property search_paths in jmeter.properties. Do not use lib/ext for utility jars; it is only intended for JMeter components.

Other jars (such as JDBC, JavaMail, Beanshell and any other support libaries needed by the JMeter code) should be placed in the lib directory - not the lib/ext directory

Note: JMeter will only find .jar files, not .zip.

You can also install utility Jar files in $JAVA_HOME/jre/lib/ext, or (since 2.1.1) you can set the property user.classpath in jmeter.properties

Note that setting the CLASSPATH environment variable will have no effect. This is because JMeter is started with "java -jar", and the java command silently ignores the CLASSPATH variable, and the -classpath/-cp options when -jar is used. [This occurs with all Java programs, not just JMeter.]

2.4.2 Using a Proxy Server

If you are testing from behind a firewall/proxy server, you may need to provide JMeter with the firewall/proxy server hostname and port number. To do so, run the jmeter.bat/jmeter file from a command line with the following parameters:

-H [proxy server hostname or ip address] -P [proxy server port] -N [nonproxy hosts] (e.g. *.apache.org|localhost) -u [username for proxy authentication - if required] -a [password for proxy authentication - if required]

Example : jmeter -H my.proxy.server -P 8000 -u username -a password -N localhost

Alternatively, you can use --proxyHost, --proxyPort, --username, and --password

JMeter also has its own in-built HTTP Proxy Server , which

can be used for recording HTTP (but not HTTPS) browser sessions. This is not to be confused with the proxy settings described above, which are used when JMeter makes HTTP or HTTPS requests itself.

2.4.3 Non-GUI Mode (Command Line mode)

For non-interactive testing, you may choose to run JMeter without the GUI. To do so, use the following command options

-n This specifies JMeter is to run in non-gui mode

-t [name of JMX file that contains the Test Plan].

-l [name of JTL file to log sample results to].

-r Run the test in the servers specified by the JMeter property "remote_hosts"

-R [list of remote servers] Run the test in the specified remote servers

The script also lets you specify the optional firewall/proxy server information:

-H [proxy server hostname or ip address] -P [proxy server port]

Example : jmeter -n -t my_test.jmx -l log.jtl -H my.proxy.server -P 8000

2.4.4 Server Mode

For distributed testing , run JMeter in server mode on the remote node(s), and then control the server(s) from the GUI. You can also use non-GUI mode to run remote tests. To start the server(s), run jmeter-server/jmeter-server.bat on each server host.

The script also lets you specify the optional firewall/proxy

server information:

-H [proxy server hostname or ip address] -P [proxy server port]

Example : jmeter-server -H my.proxy.server -P 8000

If you want the server to exit after a single test has been run, then define the JMeter property server.exitaftertest=true.

To run the test from the client in non-GUI mode, use the following command:

jmeter -n -t testplan.jmx -r [-Gprop=val] [-Z]where:-G is used to define JMeter properties to be set in the servers-X means exit the servers at the end of the test-Rserver1,server2 - can be used instead of -r to provide a list of servers to start Overrides remote_hosts, but does not define the property.

2.4.5 Overriding Properties Via The Command Line Java system properties, JMeter properties, and logging properties can be overriden directly on the command line (instead of modifying jmeter.properties). To do so, use the following options:

-D[prop_name]=[value] - defines a java system property value.

-J[prop name]=[value] - defines a local JMeter property.

-G[prop name]=[value] - defines a JMeter property to be sent to all remote servers.

-L[category]=[priority] - overrides a logging setting, setting a particular category to the given priority level.

The -L flag can also be used without the category name to set the root logging level.

Examples :

jmeter -Duser.dir=/home/mstover/jmeter_stuff \ -Jremote_hosts=127.0.0.1 -Ljmeter.engine=DEBUG

jmeter -LDEBUG

N.B. The command line properties are processed early in startup, but after the logging system has been set up. Attempts to use the -J flag to update log_level or log_file properties will have no effect.

2.4.6 Logging and error messages

JMeter does not generally use pop-up dialog boxes for errors, as these would interfere with running tests. Nor does it report any error for a mis-spelt variable or function; instead the reference is just used as is. See Functions and Variables for more information .

If JMeter detects an error during a test, a message will be written to the log file. The log file name is defined in the jmeter.properties file (or using the -j option, see below). It defaults to jmeter.log , and will be found in the directory from which JMeter was launched. [in JMeter 2.2 and earlier, this was forced to be the JMeter bin directory.]

JMeter versions after 2.2 added a new command-line option, -j jmeterlogfile. This is processed after the initial properties file is read, and before any further properties are processed. It therefore allows the default of jmeter.log to be overridden. The jmeter scripts that take a test plan name as a parameter (e.g. jmeter-n.cmd) have been updated to define the log file using the test plan name, e.g. for the test plan Test27.jmx the log file is set to Test27.log.

When running on Windows, the file may appear as just jmeter unless you have set Windows to show file extensions. [Which

you should do anyway, to make it easier to detect viruses and other nasties that pretend to be text files...]

As well as recording errors, the jmeter.log file records some information about the test run. For example:

10/17/2003 12:19:20 PM INFO - jmeter.JMeter: Version 1.9.20031002 10/17/2003 12:19:45 PM INFO - jmeter.gui.action.Load: Loading file: c:\mytestfiles\BSH.jmx 10/17/2003 12:19:52 PM INFO - jmeter.engine.StandardJMeterEngine: Running the test! 10/17/2003 12:19:52 PM INFO - jmeter.engine.StandardJMeterEngine: Starting 1 threads for group BSH. Ramp up = 1. 10/17/2003 12:19:52 PM INFO - jmeter.engine.StandardJMeterEngine: Continue on error 10/17/2003 12:19:52 PM INFO - jmeter.threads.JMeterThread: Thread BSH1-1 started 10/17/2003 12:19:52 PM INFO - jmeter.threads.JMeterThread: Thread BSH1-1 is done 10/17/2003 12:19:52 PM INFO - jmeter.engine.StandardJMeterEngine: Test has ended

The log file can be helpful in determining the cause of an error, as JMeter does not interrupt a test to display an error dialogue.

2.4.7 Full list of command-line options Invoking JMeter as "jmeter -?" will print a list of all the command-line options. These are shown below.

-h, --help print usage information and exit -v, --version print the version information and exit -p, --propfile {argument} the jmeter property file to use -q, --addprop {argument} additional property file(s)

-t, --testfile {argument} the jmeter test(.jmx) file to run -j, --jmeterlogfile {argument} the jmeter log file -l, --logfile {argument} the file to log samples to -n, --nongui run JMeter in nongui mode -s, --server run the JMeter server -H, --proxyHost {argument} Set a proxy server for JMeter to use -P, --proxyPort {argument} Set proxy server port for JMeter to use -u, --username {argument} Set username for proxy server that JMeter is to use -a, --password {argument} Set password for proxy server that JMeter is to use -J, --jmeterproperty {argument}={value} Define additional JMeter properties -G, --globalproperty (argument)[=(value)] Define Global properties (sent to servers) e.g. -Gport=123 or -Gglobal.properties -D, --systemproperty {argument}={value} Define additional System properties -S, --systemPropertyFile {filename} a property file to be added as System properties -L, --loglevel {argument}={value} Define loglevel: [category=]level e.g. jorphan=INFO or jmeter.util=DEBUG -r, --runremote (non-GUI only) Start remote servers (as defined by the jmeter property remote_hosts) -R, --remotestart server1,... (non-GUI only) Start these remote servers (overrides remote_hosts) -d, --homedir {argument} the jmeter home directory to use -X, --remoteexit Exit the remote servers at end of test (non-GUI)

Note: the JMeter log file name is formatted as a SimpleDateFormat (applied to the current date) if it contains paired single-quotes, .e.g. 'jmeter_'yyyyMMddHHmmss'.log'

If the special name LAST is used for the -t, -j or -l flags, then JMeter takes that to mean the last test plan that was run in interactive mode.

2.5 Configuring JMeter

If you wish to modify the properties with which JMeter runs you need to either modify the jmeter.properties in the /bin directory or create your own copy of the jmeter.properties and specify it in the command line.

Note: since 2.2, you can define additional JMeter properties in the file defined by the JMeter property user.properties which has the default value user.properties . The file will be automatically loaded if it is found in the current directory or if it is found in the JMeter bin directory. Similarly, system.properties is used to update system properties.

Parameters

Attribute Description Required

ssl.provider

You can specify the class for your SSL implementation if you don't want to use the built-in Java implementation.

No

xml.parser

You can specify an implementation as your XML parser. The default value is: org.apache.xerces.parsers.SAXParser

No

remote_hosts Comma-delimited list of remote JMeter hosts (or host:port if

No

required). If you are running JMeter in a distributed environment, list the machines where you have JMeter remote servers running. This will allow you to control those servers from this machine's GUI

not_in_menu

A list of components you do not want to see in JMeter's menus. As JMeter has more and more components added, you may wish to customize your JMeter to show only those components you are interested in. You may list their classname or their class label (the string that appears in JMeter's UI) here, and they will no longer appear in the menus.

No

search_paths

List of paths (separated by ;) that JMeter will search for JMeter add-on classes; for example additional samplers. This is in addition to any jars found in the lib/ext directory.

No

user.classpath

List of paths that JMeter will search for utility classes. This is in addition to any jars found in the lib directory.

No

user.properties

Name of file containing additional JMeter properties. These are added after the initial property file, but before the -q and -J options are processed.

No

system.properties

Name of file containing additional system properties. These are added before the -S and -D options are processed.

No

See also the comments in the jmeter.properties, user.properties and system.properties files for further information on other settings you can change.

Index Next Prev

3. Building a Test Plan

A test plan describes a series of steps JMeter will execute when run. A complete test plan will consist of one or more Thread Groups, logic conrollers, sample generating controllers, listeners, timers, assertions, and configuration elements.

3.1 Adding and Removing Elements

Adding elements to a test plan can be done by right-clicking on an element in the tree, and choosing a new element from the "add" list. Alternatively, elements can be loaded from file and added by choosing the "open" option.

To remove an element, make sure the element is selected, right-click on the element, and choose the "remove" option.

3.2 Loading and Saving Elements

To load an element from file, right click on the existing tree element to which you want to add the loaded element, and select the "open" option. Choose the file where your elements are saved. JMeter will load the elements into the tree.

To save tree elements, right click on an element and choose the "save" option. JMeter will save the element selected, plus all child elements beneath it. In this way, you can save test tree fragments, individual elements, or the entire test plan.

The workbench is not automatically saved with the test plan, but it can be saved separately as above.

3.3 Configuring Tree Elements

Any element in the test tree will present controls in JMeter's right-hand frame. These controls allow you to configure the behavior of that particular test element. What can be configured for an element depends on what type of element it is.

The Test Tree itself can be manipulated by dragging and dropping components around the test tree.

3.4 Saving the Test Plan

Although it is not required, we recommend that you save the Test Plan to a file before running it. To save the Test Plan, select Save Test Plan from the File menu (with the latest release, it is no longer necessary to select the Test Plan element first).

JMeter allows you to save the entire Test Plan tree or only a portion of it. To save only the elements located in a particular "branch" of the Test Plan tree, select the Test Plan element in the tree from which to start the "branch", and then click your right mouse button to access the Save As menu item. Alternatively, select the appropriate Test Plan element and then select Save As from the Edit menu.

3.5 Running a Test Plan

To run your test plan, choose "start" from the "run" menu item. To stop your test plan, choose "stop" from the same menu. When JMeter is running, it shows a small green box at the right hand end of the section just under the menu bar. You can also check the "run" menu. If "start" is disabled, and "stop" is enabled, then JMeter is running your test plan (or, at least, it thinks it is).

There are two types of stop command:

• Stop (Control + '.') - stops the threads immediately

• Shutdown (Control + ',')- requests the threads to stop at the end of any current work

3.6 Scoping Rules

The JMeter test tree contains elements that are both hierarchical and ordered. Some elements in the test trees are strictly hierarchical (Listeners, Config Elements, Post-Procesors, Pre-Processors, Assertions, Timers), and some are primarily ordered (controllers, samplers). When you create

your test plan, you will create an ordered list of sample request (via Samplers) that represent a set of steps to be executed. These requests are often organized within controllers that are also ordered. Given the following test tree:

Example test tree

The order of requests will be, One, Two, Three, Four.

Some controllers affect the order of their subelements, and you can read about these specific controllers in the component reference .

Other elements are hierarchical. An Assertion, for instance, is hierarchical in the test tree. If its parent is a request, then it is applied to that request. If its parent is a Controller, then it affects all requests that are descendants of that Controller. In the following test tree:

Hierarchy example

Assertion #1 is applied only to Request One, while Assertion #2 is applied to Requests Two and Three.

Another example, this time using Timers:

complex example

In this example, the requests are named to reflect the order in which they will be executed. Timer #1 will apply to Requests Two, Three, and Four (notice how order is irrelevant for hierarchical elements). Assertion #1 will apply only to Request Three. Timer #2 will affect all the requests.

Hopefully these examples make it clear how configuration (hierarchical) elements are applied. If you imagine each Request being passed up the tree branches, to its parent, then to its parent's parent, etc, and each time collecting all the configuration elements of that parent, then you will see how it

works.

The Configuration elements Header Manager, Cookie Manager and Authorization manager are treated differently from the Configuration Default elements. The settings from the Configuration Default elements are merged into a set of values that the Sampler has access to. However, the settings from the Managers are not merged. If more than one Manager is in the scope of a Sampler, only one Manager is used, but there is currently no way to specify which is used.

3.7 Error reporting

JMeter reports warnings and errors to the jmeter.log file, as well as some information on the test run itself. Just occasionally there may be some errors that JMeter is unable to trap and log; these will appear on the command console. If a test is not behaving as you expect, please check the log file in case any errors have been reported (e.g. perhaps a syntax error in a function call).

Sampling errors (e.g. HTTP 404 - file not found) are not normally reported in the log file. Instead these are stored as attributes of the sample result. The status of a sample result can be seen in the various different Listeners.

4. Elements of a Test Plan

The Test Plan object has a checkbox called "Functional Testing". If selected, it will cause JMeter to record the data returned from the server for each sample. If you have selected a file in your test listeners, this data will be written to file. This can be useful if you are doing a small run to ensure that JMeter is configured correctly, and that your server is returning the expected results. The consequence is that the file will grow huge quickly, and JMeter's performance will suffer. This option should be off if you are doing stress-testing (it is off by default).

If you are not recording the data to file, this option makes no difference.

You can also use the Configuration button on a listener to decide what fields to save.

4.1 ThreadGroup

Thread group elements are the beginning points of any test plan. All controllers and samplers must be under a thread group. Other elements, e.g. Listeners, may be placed directly under the test plan, in which case they will apply to all the thread groups. As the name implies, the thread group element controls the number of threads JMeter will use to execute your test. The controls for a thread group allow you to:

• Set the number of threads • Set the ramp-up period • Set the number of times to execute the test

Each thread will execute the test plan in its entirety and completely independently of other test threads. Multiple threads are used to simulate concurrent connections to your server application.

The ramp-up period tells JMeter how long to take to "ramp-up" to the full number of threads chosen. If 10 threads are used, and the ramp-up period is 100 seconds, then JMeter will take 100 seconds to get all 10 threads up and running. Each thread will start 10 (100/10) seconds after the previous thread was begun. If there are 30 threads and a ramp-up period of 120 seconds, then each successive thread will be delayed by 4 seconds.

Ramp-up needs to be long enough to avoid too large a work-load at the start of a test, and short enough that the last threads start running before the first ones finish (unless one wants that to happen).

Start with Ramp-up = number of threads and adjust up or down as needed.

By default, the thread group is configured to loop once through its elements.

Version 1.9 introduces a test run scheduler . Click the checkbox at the bottom of the Thread Group panel to reveal extra fields in which you can enter the start and end times of the run. When the test is started, JMeter will wait if necessary until the start-time has been reached. At the end of each cycle, JMeter checks if the end-time has been reached, and if so, the run is stopped, otherwise the test is allowed to continue until the iteration limit is reached.

About

• Overview • Changes • Known Bugs • License • Contributors

Download

• Download Releases

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Documentation

• User Manual • Javadocs • Localisation

(Translator's Guide)

• Building JMeter and Add-Ons

• JMeter Wiki • FAQ (Wiki)

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• Distributed Testing

• Recording Tests

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Sampler • Extending

JMeter

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• Get Involved • Mailing Lists

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Index Next Prev

• 18.1 Samplers o FTP Request o HTTP Request o JDBC Request o Java Request o SOAP/XML-RPC Request o WebService(SOAP) Request o LDAP Request o LDAP Extended Request o Access Log Sampler o BeanShell Sampler o BSF Sampler o TCP Sampler o JMS Publisher o JMS Subscriber o JMS Point-to-Point o JUnit Request o Mail Reader Sampler o Test Action

• 18.2 Logic Controllers o Simple Controller o Loop Controller o Once Only Controller o Interleave Controller o Random Controller o Random Order Controller o Throughput Controller o Runtime Controller o If Controller o While Controller o Switch Controller o ForEach Controller o Module Controller o Include Controller o Transaction Controller o Recording Controller

• 18.3 Listeners o Sample Result Save Configuration o Graph Full Results o Graph Results o Spline Visualizer o Assertion Results o View Results Tree

Copyright © 1999-2008, Apache Software Foundation

Functions and Variables

JMeter functions are special values that can populate fields of any Sampler or other element in a test tree. A function call looks like this:

${__functionName(var1,var2,var3)}

Where "__functionName" matches the name of a function. Parentheses surround the parameters sent to the function, for example ${__time(YMD)} The actual parameters vary from function to function. Functions that require no parameters can leave off the parentheses, for example ${__threadNum}.

If a function parameter contains a comma, then be sure to escape this with "\", otherwise JMeter will treat it as a parameter delimiter. For example:

${__time(EEE\, d MMM yyyy)}

Variables are referenced as follows:

${VARIABLE}

If an undefined function or variable is referenced, JMeter does not report/log an error - the reference is returned unchanged. For example if UNDEF is not defined as a variable, then the value of ${UNDEF} is ${UNDEF}. Variables, functions (and properties) are all case-sensitive. Versions of JMeter after 2.3.1 trim spaces from variable names before use, so for example ${__Random(1,63, LOTTERY )} will use the variable 'LOTTERY' rather than ' LOTTERY '.

Properties are not the same as variables. Variables are local to a thread; properties are common to all threads, and need to be referenced using the __P or __property function.

List of functions, loosely grouped into types.

Type of function Name Comment Information threadNum get thread number

Information machineName get the local machine name

Information time return current time in various formats

Information log log (or display) a message (and return the value)

Information logn log (or display) a message (empty return value)

Input StringFromFile read a line from a file

Input CSVRead read from CSV delimited file

Input XPath Use an XPath expression to read from a file

Calculation counter generate an incrementing number

Calculation intSum add int numbers

Calculation longSum add long numbers

Calculation Random generate a random number

Calculation regexFunction parse previous response using a regular expression

Scripting BeanShell run a BeanShell script

Scripting javaScript process JavaScript (Mozilla Rhino)

Scripting jexl evaluate a Commons Jexl expression

Properties property read a property

Properties P read a property (shorthand method)

Properties setProperty set a JMeter property

Variables split Split a string into variables

Variables V evaluate a variable name

Variables eval evaluate a variable expression

Variables evalVar evaluate an expression stored in a variable

19.1 What can functions do There are two kinds of functions: user-defined static values (or variables), and built-in functions. User-defined static values allow the user to define variables to be replaced with their static value when a test tree is compiled and submitted to be run. This replacement happens once at the beginning of the test run. This could be used to replace the DOMAIN field of all HTTP requests, for example - making it a simple matter to change a test to target a different server with the same test.

Note that variables cannot currently be nested; i.e ${Var${N}} does not work. The __V (variable) function (versions after 2.2) can be used to do this: ${__V(Var${N})}. In earlier JMeter versions one can use ${__BeanShell(vars.get("Var${N}")}.

This type of replacement is possible without functions, but was less convenient and less intuitive. It required users to create default config elements that would fill in blank values of Samplers. Variables allow one to replace only part of any given value, not just filling in blank values.

With built-in functions users can compute new values at run-time based on previous response data, which thread the function is in, the time, and many other sources. These values are generated fresh for every request throughout the course of the test.

Functions are shared between threads. Each occurrence of a function call in a test plan is handled by a separate function instance.

19.2 Where can functions and variables be used? Functions and variables can be written into any field of any test component (apart from the TestPlan - see below). Some fields do not allow random strings because they are expecting numbers, and thus will not accept a function. However, most fields will allow functions.

Functions which are used on the Test Plan have some restrictions. JMeter thread variables will have not been fully set up when the functions are processed, so variable names passed as parameters will not be set up, and variable references will not work, so split() and regex() and the variable evaluation functions won't work. The threadNum() function won't work (and does not make sense at test plan level). The following functions should work OK on the test plan:

• intSum • longSum • machineName • BeanShell • javaScript • jexl • random • time • property functions • log functions

Configuration elements are processed by a separate thread. Therefore functions such as __threadNum do not work properly in elements such as User Defined Variables. Also note that variables defined in a UDV element are not available until the element has been processed.

When using variable/function references in SQL code (etc), remember to include any necessary quotes for text strings, i.e. use SELECT item from table where name='${VAR}' not SELECT item from table where name=${VAR}

(unless VAR itself contains the quotes)

19.3 How to reference variables and functions Referencing a variable in a test element is done by bracketing the variable name with '${' and '}'.

Functions are referenced in the same manner, but by convention, the names of functions begin with "__" to avoid conflict with user value names * . Some functions take arguments to configure them, and these go in parentheses, comma-delimited. If the function takes no arguments, the parentheses can be omitted.

Argument values that themselves contain commas should be escaped as necessary. If you need to

include a comma in your parameter value, escape it like so: '\,'. This applies for example to the scripting functions - Javascript, Beanshell, Jexl - where it is necessary to escape any commas that may be needed in script method calls - e.g.

${__BeanShell(vars.put("name"\,"value"))}

Functions can reference variables and other functions, for example ${__XPath(${__P(xpath.file),${XPATH})} will use the property "xpath.file" as the file name and the contents of the variable XPATH as the expression to search for.

JMeter provides a tool to help you construct function calls for various built-in functions, which you can then copy-paste. It will not automatically escape values for you, since functions can be parameters to other functions, and you should only escape values you intend as literal.

The value of a variable or function can be reported using the __logn() function. The __logn() function reference can be used anywhere in the test plan after the variable has been defined. Alternatively, the Java Request sampler can be used to create a sample containing variable references; the output will be shown in the appropriate Listener. For versions of JMeter later than 2.3, there is a Debug Sampler that can be used to display the values of variables etc in the Tree View Listener.

* If you define a user-defined static variable with the same name as a built-in function, your static variable will override the built-in function.

19.4 The Function Helper Dialog The Function Helper dialog is available from JMeter's Tools menu.

Function Helper Dialog

Using the Function Helper, you can select a function from the pull down, and assign values for its arguments. The left column in the table provides a brief description of the argument, and the right column is where you write in the value for that argument. Different functions take different arguments.

Once you have done this, click the "generate" button, and the appropriate string is generated for you to copy-paste into your test plan wherever you like.

19.5 Functions

19.5.1 __regexFunctionThe Regex Function is used to parse the previous response (or the value of a variable) using any regular expression (provided by user). The function returns the template string with variable values filled in.

The __regexFunction can also store values for future use. In the sixth parameter, you can specify a reference name. After this function executes, the same values can be retrieved at later times using the syntax for user-defined values. For instance, if you enter "refName" as the sixth parameter you will be able to use:

• ${refName} to refer to the computed result of the second parameter ("Template for the replacement string") parsed by this function

• ${refName_g0} to refer to the entire match parsed by this function. • ${refName_g1} to refer to the first group parsed by this function. • ${refName_g#} to refer to the n th group parsed by this function. • ${refName_matchNr} to refer to the number of groups found by this function.

Parameters

Attribute Description Required

First argument

The first argument is the regular expression to be applied to the response data. It will grab all matches. Any parts of this expression that you wish to use in your template string, be sure to surround in parentheses. Example: <a href="(.*)">. This will grab the value of the link and store it as the first group (there is only 1 group). Another example: <input type="hidden" name="(.*)" value="(.*)">. This will grab the name as the first group, and the value as the second group. These values can be used in your template string

Yes

Second argument

This is the template string that will replace the function at run-time. To refer to a group captured in the regular expression, use the syntax: $[group_number]$. Ie: $1$, or $2$. Your template can be any string.

Yes

Third argument

The third argument tells JMeter which match to use. Your regular expression might find numerous matches. You have four choices:

• An integer - Tells JMeter to use that match. '1' for the first found match, '2' for the second, and so on

• RAND - Tells JMeter to choose a match at random. • ALL - Tells JMeter to use all matches, and create a template

string for each one and then append them all together. This option is little used.

• A float number between 0 and 1 - tells JMeter to find the Xth match using the formula: (number_of_matches_found * float_number) rounded to nearest integer.

No, default=1

Fourth If 'ALL' was selected for the above argument value, then this argument

19.6 Pre-defined Variables Most variables are set by calling functions or by test elements such as User Defined Variables; in which case the user has full control over the variable name that is used. However some variables are defined internally by JMeter. These are listed below.

• cookiename - contains the cookie value • JMeterThread.last_sample_ok - whether or not the last sample was OK - true/false

• START variables (see next section)

19.6 Pre-defined Properties The set of JMeter properties is initialised from the system properties defined when JMeter starts; additional JMeter properties are defined in jmeter.properties, user.properties or on the command line.

Some built-in properties are defined by JMeter. These are listed below. For convenience, the START properties are also copied to variables with the same names.

• START.MS - JMeter start time in milliseconds • START.YMD - JMeter start time as yyyyMMdd • START.HMS - JMeter start time as HHmmss • TESTSTART.MS - test start time in milliseconds

Please note that the START variables / properties represent JMeter startup time, not the test start time. They are mainly intended for use in file names etc.

Regular Expressions 20.1 Overview JMeter includes the pattern matching software Apache Jakarta ORO There is some documentation for this on the Jakarta web-site, for example a summary of the pattern matching characters

There is also documentation on an older incarnation of the product at OROMatcher User's guide , which might prove useful.

The pattern matching is very similar to the pattern matching in Perl. A full installation of Perl will include plenty of documentation on regular expressions - look for perlrequick, perlretut, perlre, perlreref.

It is worth stressing the difference between "contains" and "matches", as used on the Response Assertion test element:

• "contains" means that the regular expression matched at least some part of the target, so 'alphabet' "contains" 'ph.b.' because the regular expression matches the substring 'phabe'. • "matches" means that the regular expression matched the whole target. So 'alphabet' is "matched" by 'al.*t'.

In this case, it is equivalent to wrapping the regular expression in ^ and $, viz '^al.*t$'.

However, this is not always the case. For example, the regular expression 'alp|.lp.*' is "contained" in 'alphabet', but does not match 'alphabet'.

Why? Because when the pattern matcher finds the sequence 'alp' in 'alphabet', it stops trying any other combinations - and 'alp' is not the same as 'alphabet', as it does not include 'habet'.

Note: unlike Perl, there is no need to (i.e. do not) enclose the regular expression in //.

So how does one use the modifiers ismx etc if there is no trailing /? The solution is to use extended regular expressions , i.e. /abc/i becomes (?i)abc. See also Placement of modifiers below.

20.2 Examples Extract single string Suppose you want to match the following portion of a web-page: name="file" value="readme.txt" and you want to extract readme.txt. A suitable reqular expression would be: name="file" value="(.+?)"

The special characters above are:

• ( and ) - these enclose the portion of the match string to be returned • . - match any character. + - one or more times. ? - don't be greedy, i.e. stop when first match succeeds

Note: without the ?, the .+ would continue past the first " until it found the last possible " - probably not what was intended.

Extract multiple strings

Suppose you want to match the following portion of a web-page: name="file.name" value="readme.txt" and you want to extract file.name and readme.txt. A suitable reqular expression would be: name="(.+?)" value="(.+?)" This would create 2 groups, which could be used in the JMeter Regular Expression Extractor template as $1$ and $2$.

The JMeter Regex Extractor saves the values of the groups in additional variables.

For example, assume:

• Reference Name: MYREF • Regex: name="(.+?)" value="(.+?)" • Template: $1$$2$

Do not enclose the regular expression in / /

The following variables would be set:

• MYREF: file.namereadme.txt • MYREF_g0: name="file.name" value="readme.txt" • MYREF_g1: file.name • MYREF_g2: readme.txt

These variables can be referred to later on in the JMeter test plan, as ${MYREF}, ${MYREF_g1} etc

20.3 Line mode The pattern matching behaves in various slightly different ways, depending on the setting of the multi-line and single-line modifiers. Note that the single-line and multi-line operators have nothing to do with each other; they can be specified independently.

Single-line mode

Single-line mode only affects how the '.' meta-character is interpreted.

Default behaviour is that '.' matches any character except newline. In single-line mode, '.' also matches newline.

Multi-line mode

Multi-line mode only affects how the meta-characters '^' and '$' are interpreted.

Default behaviour is that '^' and '$' only match at the very beginning and end of the string. When Multi-line mode is used, the '^' metacharacter matches at the beginning of every line, and the '$' metacharacter matches at the end of every line.

20.4 Meta characters Regular expressions use certain characters as meta characters - these characters have a special meaning to the RE engine. Such characters must be escaped by preceeding them with \

(backslash) in order to treat them as ordinary characters. Here is a list of the meta characters and their meaning (please check the ORO documentation if in doubt).

• ( ) - grouping • [ ] - character classes • { } - repetition • * + ? - repetition • . - wild-card character • \ - escape character • | - alternatives • ^ $ - start and end of string or line

Please note that ORO does not support the \Q and \E meta-characters. [In other RE engines, these can be used to quote a portion of an RE so that the meta-characters stand for themselves.]

20.5 Placement of modifiers Modifiers can be placed anywhere in the regex, and apply from that point onwards. [A bug in ORO means that they cannot be used at the very end of the regex. However they would have no effect there anyway.]

The single-line (?s) and multi-line (?m) modifiers are normally placed at the start of the regex.

The ignore-case modifier (?i) may be usefully applied to just part of a regex, for example:

Match ExAct case or (?i)ArBiTrARY(?-i) case

Glossary

Latency . JMeter measures the latency from just before sending the request to just after the first response has been received. Thus the time includes all the processing needed to assemble the request as well as assembling the response, which in general will be longer than one byte. Protocol analysers (such as Wireshark) measure the time when bytes are actually sent/received over the interface. The JMeter time should be closer to that which is experienced by a browser or other application client.

Median is a number which divides the samples into two equal halves. Half of the samples are smaller than the median, and half are larger. [Some samples may equal the median.] This is a standard statistical measure. See, for example: Median entry at Wikipedia. The Median is the same as the 50 th Percentile

90% Line (90 th Percentile) is the value below which 90% of the samples fall. The remaining samples too at least as long as the value. This is a standard statistical measure. See, for example: Percentile entry at Wikipedia.

Throughput is calculated as requests/unit of time. The time is calculated from the start of the first sample to the end of the last sample. This includes any intervals between samples.