Changes
Earlier changes are detailed in the History of Previous Changes.
Version 5.5
Summary
- New and Noteworthy
- Incompatible changes
- Bug fixes
- Improvements
- Non-functional changes
- Known problems and workarounds
- Thanks
New and Noteworthy
JMeter now supports Java 17
JMeter 5.5 ships with log4j2 2.17.2
Open Model Thread Group
New component: Open Model Thread Group allows creating load profiles with variable load.
For example, if you need to gradually increase load from 0/sec to 10/sec during minute you could previously use Thread Group + Timer combinations. However, then you need to compute the expected number of threads, ensure they are created only when needed, and so on.
With Open Model Thread Group you can configure the same load profile as rate(0/sec) random_arrivals(1 minute) rate(10/sec). The thread group would spawn threads as needed to drive the configured load. The load profile can use properties, so you can launch the same script with slightly different load levels, however, the profile can't be updated while the test is running.
The new thread group is experimental in JMeter 5.5, so please feel free to submit your feedback.

Preparing the deprecation of Oro Regex usage
Another experimental feature in JMeter 5.5 is the ability to replace the Oro based Regex implementation by the built-in Java based one. To choose the Java based one, set the JMeter property jmeter.regex.engine to the value java.
Core improvements
Kotlin language is now used in some core classes and tests (e.g. Open Model Thread Group). JMeter is compiled with apiTarget=1.5, and it ships with kotlin-stdlib 1.6.
lets-plot-kotlin charting library is added, so it will be easier to refine and create new charts in UI in the future.
Improvements
Thread Groups
- New component: Open Model Thread Group
HTTP Samplers and Test Script Recorder
- Bug 65027 - Detect mime-type for files automatically when adding files to HTTP Sampler
- Bug 65020 - HTTP Sampler/Files upload tab – add missing buttons
- Pull request #650 - HTTP Sampler timestamp fix when exception is caught. Contributed by Konstantin Kalinin (konstantin at kkalinin.pro)
- Bug 65328 - Pull request #666 - HTTP 308 Permanent Redirect is not supported. Contributed by Baptiste Gaillard (baptiste.gaillard at gmail.com)
Other samplers
- Bug 65149 - Pull request #644 - Encode the personal part of email addresses in SMTP Sampler
- Pull request #638 - Various additions to the Bolt Sampler. Added transaction timeout, database option required for Neo4j 4.x (with multi-database support) and access mode option, that allows running against a Neo4j Enterprise Causal Cluster. Contributed by David Pecollet (david.pecollet at gmail.com)
Controllers
- Pull request #665 - Increase visible lines of code in IfController and WhileController. Based on an idea by David Getzlaff (david.getzlaff at t-systems.com>).
Listeners
- Bug 64988 - Sort properties and variables in a human expected order for DebugPostProcessor and DebugSampler
- Bug 63061 - Sort View Results in Table in a human expected order
- Pull request #706 - Try to keep UI responsive when displaying large text results. Can be configured with the new property view.results.tree.simple_view_limit
Timers, Assertions, Config, Pre- & Post-Processors
- Pull request #638 - Bolt Connection Configuration: added ConnectionPoolMaxSize parameter. Contributed by David Pecollet (david.pecollet at gmail.com)
- Bug 65515 - Allow pooling of Prepared Statements in JDBC
- Bug 65299 - JSONPathAssertion attributes are out of order/Compare JSON objects and not their string representations.
Report / Dashboard
- Bug 65353 - Make the estimator used for calculating percentiles on the dashboard configurable
General
- Bug 61805 - Pull request #663 - Add simple HTTP request template. Contributed by Ori Marko (orimarko at gmail.com)
- Bug 65611 - Pull request #673 - Add support for IPv6 addresses when specifying a remote worker node. Based on a patch by Peter Wong (peter.wong at csexperts.com)
- Reduce memory consumption by the logging panel (disable undo events for it)
- Bug 63620 - Pull request #694 - Fix GUI freeze when viewing response body with long line breaks
- Pull request #699 - Add documentation for Graphite Backend Listener. Contributed by Ji Hun (jihunkimkw at gmail.com)
- Bug 57672 - Pull request #700 - Add a switch (jmeter.regex.engine) to replace Oro Regex implementation by the built-in Java one.
Non-functional changes
- Added Kotlin 1.6.21 for JMeter engine implementation (apiVersion=1.5). The set of JSR 223 languages is intact.
- Bug 65128 - Pull request #643 - Add missing documentation about Same user on each iteration for Thread Groups. Contributed by njkuzas.
- Pull request #648 - Updated xmlgraphics-commons to 2.6 (from 2.3). Contributed by Stefan Seide (stefan at trilobyte-se.de)
- Pull request #655, Pull request #667, Pull request #675, Pull request #698 - Updated x-stream to 1.4.19 (from 1.4.15). Contributed by Stefan Seide (stefan at trilobyte-se.de)
- Pull request #656, Pull request #668 - Updated json-smart to 2.4.8 (from 2.3), accessors-smart to 2.4.8 (from 1.2) and asm 9.3 (from 9.0). Contributed by Stefan Seide (stefan at trilobyte-se.de)
- Bug 64831 - Log truststore entries in debug level for logger org.apache.jmeter.util.keystore.JmeterKeyStore
- Bug 65232 - Hide splash screen when an error is displayed because the test plan could not be parsed.
- Updated Groovy to 3.0.11 (from 3.0.7).
- Updated Darklaf to 2.7.3 (from 2.5.4).
- Updated Apache ActiveMQ to 15.6.4 (from 15.6.0).
- Updated Asm to 9.2 (from 9.1).
- Updated Bouncycastle to 1.70 (from 1.67).
- Updated Caffeine to 2.9.3 (from 2.8.8).
- Updated Apache commons-dbcp2 to 2.9.0 (from 2.8.0).
- Updated Apache commons-io to 2.11.0 (from 2.8.0).
- Updated Apache commons-lang3 to 3.12.0 (from 3.11).
- Updated Apache commons-net to 3.8.0 (from 3.7.2).
- Updated Apache commons-pool2 to 2.11.1 (from 2.9.0).
- Updated equalsverifier to 3.10 (from 3.4.2).
- Updated Apache Freemarker to 2.3.31 (from 2.3.30).
- Updated hsqldb to 2.5.2 (from 2.5.0).
- Updated Apache HttpClient to 4.5.13 (from 4.5.12).
- Updated Apache HttpCore to 4.4.15 (from 4.4.13).
- Updated jacoco to 0.8.7 (from 0.8.5).
- Updated json-path to 2.7.0 (from 2.4.0).
- Updated jsoup to 1.15.1 (from 1.13.1).
- Updated JUnit to 4.13.2 and 5.8.2 (from 4.13.1 and 5.7.0).
- Updated Apache log4j2 to 2.17.2 (from 2.13.3).
- Updated Miglayout to 5.3 (from 5.2).
- Updated Neo4j Java driver to 4.4.6 (from 4.2.0).
- Updated Objenesis to 3.2 (from 2.6).
- Updated ktlint to 0.40.0
- Updated PH CSS and PH commons to 6.5.4 and 10.1.6 (from 6.2.3 and 9.5.1).
- Updated RSyntaxTextArea to 3.2.0 (from 3.1.1).
- Updated SLF4J to 1.7.36 (from 1.7.30).
- Updated SvgSalamander to 1.1.2.4 (from 1.1.2.1).
- Pull request #698 - Updated Apache Tika to 1.28.3 (from 1.26).
- Updated WireMock-JRE8 to 2.30.0 (from 2.24.1).
- Updated com.github.vlsi.vlsi-release-plugins 1.76 (from 1.74).
- Updated jackson to 2.13.3 (from 2.10.5)
- Updated jmespath to 0.5.1
- Updated Saxon-HE to 11.2 (from 9.9.1-8)
- Updated Apache xmlgraphics commons to 2.7 (from 2.6)
- Pull request #671 - Move example definition of property jmeter.reportgenerator.statistic_window to user.properties, as it is read from that place. Contributed by Rithvik Patibandla (rithvikp98 at gmail.com)
- Bug 65456 - Updated commons-jexl 3 to 3.2.1 (from 3.1). Contributed by Ori Marko (orimarko at gmail.com>)
- Pull request #654 - Try do give better feedback while loading keystores
- Pull request #672 - Add more details to documentation for timeShift function. Contributed by Mariusz (mawasak at gmail.com)
- Updated Gradle to 7.3 (from 7.2)
- Pull request #689 - Code clean up in StringFromFile. Contributed by Sampath Kumar Krishnasamy (sampathkumar.krishnasamykuppusamy at aexp.com)
- Pull request #690 - Refactor a few unit tests. Contributed by Sampath Kumar Krishnasamy (sampathkumar.krishnasamykuppusamy at aexp.com)
- Pull request #692> - Fix a few deprecation warnings for Gradle. Contributed by Sampath Kumar Krishnasamy (sampathkumar.krishnasamykuppusamy at aexp.com)
- Pull request #697> - Junit 5 tests to use asserts from Junit 5 API. Contributed by Sampath Kumar Krishnasamy (sampathkumar.krishnasamykuppusamy at aexp.com)
- Bug 65983 - Pull request #707 - Use current screenshot for save-to-file listener in documentation. Based on patch by NaveenKumar Namachivayam (catch.nkn at gmail.com)
- Pull request #708 - Make errorprone happier. Based on patch by Wilson Kurniawan (wilson at visenze.com)>
- Updated Rhino JavaScript to 1.7.14 (from 1.7.13)
Bug fixes
HTTP Samplers and Test Script Recorder
- Bug 65310 - Don't let users override multipart/form-data content-type header in HC4 sampler.
- Bug 65363 - NullPointerException in HTTPHC4Impl$ManagedCredentialsProvider.getAuthorizationForAuthScope when 401 response from remote and httpclient4.auth.preemptive=false
- Bug 65692 - HTTP(s) Test Script Recorder: Enable setting enabled cipher suite and enabled protocols on SSLContext/ Align SSL properties between Java and HC4 implementation
- Bug 65108 - Support JMeter variables in GraphQL HTTP Request
- Bug 65864 - Catch NullPointerException from JSoup when recording a test plan
Other Samplers
- Bug 65152 - OS Process Sampler – Cannot Add from Clipboard Command parameters
- Pull request #638 - Bolt Sampler: fixed error displaying results when "Record Query Results" is enabled. Contributed by David Pecollet (david.pecollet at gmail.com)
Controllers
Listeners
- Bug 64962 - Save CSV sub-results recursively from View Results Tree
- Bug 65784 - No Graphs displayed in Aggregate Report/Response Time Graph
- Bug 65884 - GUI doesn't display response for multipart request manually encoded
Timers, Assertions, Config, Pre- & Post-Processors
- Bug 65257 - JMESPathExtractor writes error log entries if JMESPath filter returns empty result
- Bug 65259 - JMESPathExtractor Attribute Match No. Required
- Bug 65269 - JSON Extractor and JSON JMESPath Extractor ignore sub-samples
- Bug 65352 - Warning logged when Boundary Extractor doesn't find any match
- Bug 65681 - Use default values for null values when extracting with JSONPostProcessor
- Allow setters in ConstantThroughputTimer to update the values during run time
- Bug 65782 - Use correct message format for MessageFormat in HTMLAssertion
- Bug 65794 - JSON Assertion always successful with indefinite paths
Functions
I18N
Report / Dashboard
Documentation
- Pull request #658 - Improve javadoc. Contributed by Ori Marko (orimarko at gmail.com)
General
- Bug 64318 - DNS Cache Manager – custom DNS resolver does not use system resolver by default
- Pull request #641, Pull request #698 - Updated xercesImpl to 2.12.2 (from 2.12.0). Based on patch by Stefan Seide (stefan at trilobyte-se.de).
- Pull request #645 - Add escaping for new lines in AbstractInfluxdbMetricsSender. Contributed by David Getzlaff (david.getzlaff at t-systems.com>)
- Bug 65198 - Can't copy generated function from FunctionHelper
- Pull request #661 - Fix wording in doc. Contributed by BugKing (wangzhen at fit2cloud.com)
- Pull request #664 - Allow whitespace in path. Contributed by Till Neunast (github.com/tilln)
- Bug 65270 - POST application/x-www-form-urlencoded cURL code generated from Postman is not imported correctly
- Silence warnings of missing font Arial on startup under Linux
- Bug 65300 - IllegalAccessError when opening file dialog with Java 16
- Bug 65336 - Blank labels when different elements had the same name
- Bug 65522 - Restart doesn't work, when parameters contain spaces
- Bug 63914 - Simplify :src:dist:clean configuration, ensure /lib/junit/test.jar is removed on clean
- Pull request #696 - Keep JSyntaxTextArea text value for use in headless mode. Contributed by Peter Paul Bakker (peter.paul.bakker at stokpop.nl)
Thanks
We thank all contributors mentioned in bug and improvement sections above:
- Stefan Seide (stefan at trilobyte-se.de)
- njzukas (github.com/njzukas)
- David Getzlaff (david.getzlaff at t-systems.com>)
- Konstantin Kalinin (konstantin at kkalinin.pro)
- David Pecollet (david.pecollet at gmail.com)
- Ori Marko (orimarko at gmail.com)
- BugKing (wangzhen at fit2cloud.com)
- Till Neunast (github.com/tilln)
- Baptiste Gaillard (baptiste.gaillard at gmail.com)
- Rithvik Patibandla (rithvikp98 at gmail.com)
- Mariusz (mawasak at gmail.com)
- peter.wong@csexperts.com
- Woonsan Ko (woonsan.ko at bloomreach.com)
- Chromico Rek (atech5122 at gmail.com)
- Magnus Spångdal (magnus.spangdal as avanza.se)
- Piotr Smietana (piotrsmietana1998 at gmail.com)
- Sampath Kumar Krishnasamy (sampathkumar.krishnasamykuppusamy at aexp.com)
- Ji Hun (jihunkimkw at gmail.com)
- Peter Paul Bakker (peter.paul.bakker at stokpop.nl)
- NaveenKumar Namachivayam (catch.nkn at gmail.com)
- Wilson Kurniawan (wilson at visenze.com)
We also thank bug reporters who helped us improve JMeter.
- Nikola Aleksic (nalexic at gmail.com)
- Vladimir Rosu (rosuvladimir at gmail.com)
Apologies if we have omitted anyone else.
Known problems and workarounds
- The Once Only controller behaves correctly under a Thread Group or Loop Controller, but otherwise its behaviour is not consistent (or clearly specified).
- The numbers that appear to the left of the green box are the number of active threads / total number of threads, the total number of threads only applies to a locally run test, otherwise it will show 0 (see Bug 55510).
-
Note that under some windows systems you may have this WARNING:
java.util.prefs.WindowsPreferences WARNING: Could not open/create prefs root node Software\JavaSoft\Prefs at root 0 x80000002. Windows RegCreateKeyEx(…) returned error code 5.
The fix is to run JMeter as Administrator, it will create the registry key for you, then you can restart JMeter as a normal user and you won't have the warning anymore. -
You may encounter the following error:
java.security.cert.CertificateException: Certificates does not conform to algorithm constraints
if you run a HTTPS request on a web site with a SSL certificate (itself or one of SSL certificates in its chain of trust) with a signature algorithm using MD2 (like md2WithRSAEncryption) or with a SSL certificate with a size lower than 1024 bits. This error is related to increased security in Java 8+.
To allow you to perform your HTTPS request, you can downgrade the security of your Java installation by editing the Java jdk.certpath.disabledAlgorithms property. Remove the MD2 value or the constraint on size, depending on your case.
This property is in this file:JAVA_HOME/jre/lib/security/java.security
See Bug 56357 for details. - Under Mac OSX Aggregate Graph will show wrong values due to mirroring effect on numbers. This is due to a known Java bug, see Bug JDK-8065373 The fix is to use JDK8_u45 or later.
- View Results Tree may fail to display some HTML code under HTML renderer, see Bug 54586. This is due to a known Java bug which fails to parse "px" units in row/col attributes. See Bug JDK-8031109 The fix is to use JDK9 b65 or later.
- JTable selection with keyboard (SHIFT + up/down) is totally unusable with Java 7 on Mac OSX. This is due to a known Java bug JDK-8025126 The fix is to use JDK 8 b132 or later.
-
Since Java 11 the JavaScript implementation Nashorn has been deprecated.
Java will emit the following deprecation warnings, if you are using JavaScript based on Nashorn.
Warning: Nashorn engine is planned to be removed from a future JDK release
To silence these warnings, add -Dnashorn.args=--no-deprecation-warning to your Java arguments. That can be achieved by setting the enviroment variable JVM_ARGSexport JVM_ARGS="-Dnashorn.args=--no-deprecation-warning"
-
With Java 15 the JavaScript implementation Nashorn has been removed. To add back a JSR-223 compatible JavaScript engine you have two options:
- Use Mozilla Rhino
- Copy rhino-engine-1.7.14.jar into $JMETER_HOME/lib/ext.
- Use OpenJDK Nashorn
-
The OpenJDK Nashorn implementation comes as a module. To use it, you will have to download it and add it to the module path. A hacky way to download the version 15.0 (or later) and its dependencies and set the module path is outlined below:
mkdir lib/modules pushd lib/modules wget https://repo1.maven.org/maven2/org/openjdk/nashorn/nashorn-core/15.3/nashorn-core-15.3.jar wget https://repo1.maven.org/maven2/org/ow2/asm/asm/9.2/asm-9.2.jar wget https://repo1.maven.org/maven2/org/ow2/asm/asm-commons/9.2/asm-commons-9.2.jar wget https://repo1.maven.org/maven2/org/ow2/asm/asm-util/9.2/asm-util-9.2.jar wget https://repo1.maven.org/maven2/org/ow2/asm/asm-tree/9.2/asm-tree-9.2.jar wget https://repo1.maven.org/maven2/org/ow2/asm/asm-analysis/9.2/asm-analysis-9.2.jar popd export JVM_ARGS="--module-path $PWD/lib/modules" ./bin/jmeter