--- title: "JMX ThreadInfo" description: "" url: "https://docs.itrsgroup.com/docs/geneos/7.11.0/collection/jmx-threadinfo/index.html" --- ## Introduction The Geneos JMX ThreadInfo Plug-in allows for the monitoring of the thread sub-system of JMX-enabled applications. These include applications which have been written to expose their state by implementing the JMX specification, for example, Tomcat 6.0. ## Java requirements - You must have Java installed on the machine running the Netprobe. For information on supported Java versions, see [Java support in Geneos Compatibility Matrix](https://docs.itrsgroup.com/docs/all/geneos/7x-geneos-compat-matrix/index.html#java-support). - Once you have Java installed, configure the environment variables required by the Netprobe so that it can locate the required resource files. For guidance, see [Configure the Java environment](https://docs.itrsgroup.com/docs/geneos/7.11.0/collection/netprobe/configuration/configure-the-java-environment/index.html). The Java installation and environment configuration is a common source of errors for users setting up Java-based components and plug-ins. It is recommended to read [Configure the Java environment](https://docs.itrsgroup.com/docs/geneos/7.11.0/collection/netprobe/configuration/configure-the-java-environment/index.html) to help you understand your Java installation. ## Views The plug-in produces a single view, a representative example of which is given below: ![jmx-threadinfo2](https://docscdn.itrsgroup.com/geneos/images/netprobe/system-images/image2_geneos_-_jmx-threadinfo_plug-in.png) **Headline Legend**
Name Description
DaemonThreadCount the current number of live daemon threads
PeakThreadCount the peak live thread count since the Java virtual machine started or peak was reset
ThreadCount the current number of live threads including both daemon and non-daemon threads
TotalStartedThreadCount the total number of threads created and also started since the Java virtual machine started.
ThreadContentionMonitoringEnabled if thread contention monitoring is enabled
ThreadContentionMonitoringSupported if the Java virtual machine supports thread contention monitoring
ThreadCpuTimeEnabled if thread CPU time measurement is enabled.
ThreadCpuTimeSupported if the Java virtual machine implementation supports CPU time measurement for any thread
**Table Legend**
Name Description
threadName The name of a particular thread in the jvm
threadId The id for a particular thread in the jvm
threadState One of the following states: NEW, RUNNABLE, BLOCKED, WAITING, TIMED_WAITING, TERMINATED
suspended Whether the thread is suspended or not
blockedCount the total number of times that this thread blocked to enter or reenter a monitor
blockedTime the approximate accumulated elapsed time (in milliseconds) that this thread has blocked to enter or reenter a monitor since thread contention monitoring is enabled
lockOwnerId the ID of the thread which owns the object for which this thread is blocked waiting
lockOwnerName the name of the thread which owns the object for which this thread is blocked waiting
lockName the string representation of the object for which this thread is blocked waiting
waitedCount the total number of times that this thread waited for notification
waitedTime the approximate accumulated elapsed time (in milliseconds) that this thread has waited for notification since thread contention monitoring is enabled
inNative Tests if this thread is executing native code via the Java Native Interface (JNI).
threadCpuTime the total CPU time for this thread in nanoseconds
threadUserTime the CPU time that this thread has executed in user mode in nanoseconds
## Plug-in Configuration You can safely update most of the configuration options on this plug-in without causing the Netprobe to restart. The exception is the [jproperties](#jproperties) option. If you update this option, then the Netprobe restarts. ### connection Identifies the set of settings required to connect to the monitored Java application. ### connection > serviceUrl Specifies the location where the monitored application resides, e.g. ``` service:jmx:rmi:///jndi/rmi://192.168.10.161:25000/jmxrmi ``` ### connection > username Identifies a particular setting required to connect to the monitored Java application. ### connection > password Specifies the password with which to connect to a secured Java application. To set an encrypted password, click on the "Set Password" button, then enter and confirm the password to be used. ### connection > timeout Specifies the number of milliseconds to wait for connections to be established. This setting should not be used unless it is found that the sampler seems to be waiting for inordinate amounts of time to connect to an application which is clearly down. This allows a timeout which the user decides is appropriate, for which to wait for a connection, before deciding that the application should be considered down. ### headlineLabels Allows the user to configure just those headlines that they are interested in. If this section is blank, then all the headlines will be displayed in the dataview. ### headlineLabels > headlineLabel Identifies one of a prefixed set of thread attributes which should be displayed as a headline. Possible values:
Setting Description
DaemonThreadCount the current number of live daemon threads
PeakThreadCount the peak live thread count since the Java virtual machine started or peak was reset
ThreadCount the current number of live threads including both daemon and non-daemon threads
TotalStartedThreadCount the total number of threads created and also started since the Java virtual machine started.
ThreadContentionMonitoringEnabled if thread contention monitoring is enabled
ThreadContentionMonitoringSupported if the Java virtual machine supports thread contention monitoring
ThreadCpuTimeEnabled if thread CPU time measurement is enabled.
ThreadCpuTimeSupported if the Java virtual machine implementation supports CPU time measurement for any thread
Mandatory: No ### tablecolLabels Allows the user to specify one or more column headers to display. If this is not enabled then all the column headers are displayed. Mandatory: No ### tablecolLabels > tablecolLabel Identifies one of a prefixed set of thread attributes which should be displayed in a table column Possible values:
Setting Description
threadId The id for a particular thread in the jvm
threadState One of the following states: NEW, RUNNABLE, BLOCKED, WAITING, TIMED_WAITING, TERMINATED
suspended Whether the thread is suspended or not
blockedCount the total number of times that this thread blocked to enter or reenter a monitor
blockedTime the approximate accumulated elapsed time (in milliseconds) that this thread has blocked to enter or reenter a monitor since thread contention monitoring is enabled
lockOwnerId the ID of the thread which owns the object for which this thread is blocked waiting
lockOwnerName the name of the thread which owns the object for which this thread is blocked waiting
lockName the string representation of the object for which this thread is blocked waiting
waitedCount the total number of times that this thread waited for notification
waitedTime the approximate accumulated elapsed time (in milliseconds) that this thread has waited for notification since thread contention monitoring is enabled
inNative Tests if this thread is executing native code via the Java Native Interface (JNI).
threadCpuTime the total CPU time for this thread in nanoseconds
threadUserTime the CPU time that this thread has executed in user mode in nanoseconds
Mandatory: No ### jproperties Allows the user to specify additional flags with which to configure the JVM which the probe creates. **Note** Java flags that are configured on this setting are inherited by all Java-based samplers running on the same Netprobe. For a full list of Java-based plugins, see [Overview in Configure the Java environment](https://docs.itrsgroup.com/docs/geneos/7.11.0/collection/netprobe/configuration/configure-the-java-environment/index.html#overview). For example, consider the following scenario: 1. Netprobe `A` is running the JMX and REST API samplers. 2. The JMX sampler uses the `jproperties` setting to enable TSL. 3. A REST API sampler on Netprobe `A` inherits the values configured in the `jproperties` setting. It is possible that the REST API sampler may encounter errors if the `jproperties` flags require data that is not present in the REST API sampler. To address this, the JMX and REST API samplers must be run on separate Netprobes. Mandatory: No ### jproperties > jproperty Allows user to specify a comma separated list of supported JVM arguments. This comprises those flags which begin with **-D** or the **-verbose** flag. Flags starting with **-X** are JVM implementation dependent and may or may not work. For example, ``` JProperties=-Xms2M,-Xmx4M,-verbose ``` Mandatory: No ### rowLimit Specifies the maximum number of rows displayed in the dataview. Default: `200` Mandatory: No ### logJavaMemoryInfo Whether java heap usage should be logged every 10 minutes to the netprobe log file or not. Possible values:
Setting Description
true java heap usage should be logged every 10 minutes
false java heap usage should not be logged every 10 minutes
Mandatory: No Default: false ### Additional Files The plug-in requires the following files to be present in the net probe directory: ITRS provided files: 1. launchpad.jar 2. jmx-plugins.jar 3. jep-2.3.0.jar 4. launchPad.dll (Windows) or liblaunchpad.so (UNIX/LINUX) In addition, Microsoft.VC80.CRT redistributables are required when using AES-256 passwords in Windows machines. ## Current Limitations ### Attribute Types The requested attribute must be either a primitive (e.g. boolean, short, integer, long, float, double) or a reference to an object for which toString() has been overridden to provide a sensible human viewable value. If an attribute is requested which violates these constraints, then the information published to the dataview is likely to not be useful. Please see section 2.7 for some exceptions to this rule. ### Whitespaces In MBean Aliases The plug-in does not accept mbean aliases that contain leading or trailing whitespace. It does however, accept mbean aliases which contain whitespace within the actual alias. ## Connecting to applications using password and access files Java supports the use of password files and access files to restrict access to a jmx-enabled application. In this case the plugin also needs to provide a username and password before being allowed to connect to and retrieve information from the application. We explain how to configure a sample Java application for authenticated access and then show how to configure the plugin to connect to that application. The instructions given are suitable for UNIX and LINUX. Please see for instructions on how to secure an application for windows. ### Securing the application The first thing to ensure is that we have a valid rolename-permission pair in the access file that resides inside the JRE installation directory i.e. $JRE/management/jmxremote.access: By default the following rolename-permission pairs exist: ``` monitorRole readonly controlRole readwrite ``` So we add our own entry choosing **kyoto** as our rolename and granting it readwrite access. Our file should now look like this: ``` monitorRole readonly controlRole readwrite kyoto readwrite ``` We then create a local password file called *jmxremote.password* in our current working directory. We need to chmod 600 the file otherwise Java will complain and not use the file. We then add our rolename along with **origami** as the password of our choice. The jmxremote.password file should now look like this: ``` kyoto origami ``` Assuming our application is a standalone class file called *JmxServer* we can now start the application passing the following flags to the Java command: ``` java -Dcom.sun.management.jmxremote -Dcom.sun.management.jmxremote.port=5003 -Dcom.sun.management.jmxremote.ssl=false -Dcom.sun.management.jmxremote.authenticate=true -D com.sun.management.jmxremote.password.file=/jmxremote.password JmxServer ``` **Note** We have now specified true for the authenticate flag and passed in the absolute path of where to find the jmxremote.password file. Finally we configure a jmx-threadinfo plugin to connect to our secured application and retrieve some information about the threads currently running in its JVM: ``` // Sampler Descriptor Plugin=JMX-THREADINFO Settings=@Settings GroupName=JMX ViewName=THREADS HeadlineLabels=@Headlines TableColLabels=@TableCols ``` ``` // Additional Data section(Settings) ServiceURL=service:jmx:rmi:///jndi/rmi://192.168.10.200:5003/jmxrmi username=kyoto password=origami ``` **Note** When setting a password, user will have the option of entering the password in encrypted form. Plugin settings will not show the password in plaintext, but in encrypted text. ``` // Additional Data section(Headlines) DaemonThreadCount PeakThreadCount ``` ``` // Additional Data section(TableCols) threadName threadId threadState ```