What is a thread group?
A thread group represents a set of threads. In addition, a thread group can also include other thread groups. The thread groups form a tree in which every thread group except the initial thread group has a parent.
How many types of thread groups are there in JMeter?
If start value equals end value and they are let’s say 20, and you set a duration of 2 minutes this means that each minute, you get 20 new arrivals with a constant ramp-up of 3 seconds between threads….Free Form Arrivals Thread Group.
| Start Value | End Value | Duration |
|---|---|---|
| 20 | 20 | 1 |
| 10 | 10 | 1 |
How do I add a thread to a group?
To create a Thread Group it is required to have the Test Plan created.
- Start JMeter.
- Select Test Plan on the tree.
- Add Thread Group.
What are thread groups in JMeter?
Thread Groups is a collection of Threads. Each thread represents one user using the application under test. Basically, each Thread simulates one real user request to the server. The controls for a thread group allow you to Set the number of threads for each group.
Is daemon a thread?
A Daemon thread is a background service thread which runs as a low priority thread and performs background operations like garbage collection. JVM exits if only daemon threads are remaining. The setDaemon() method of the Thread class is used to mark/set a particular thread as either a daemon thread or a user thread.
What is the difference between thread pool and thread group?
Thread group class was created in JDK 1.0 to manage the state of multiple threads at once e.g suspend, resume etc. Later most of its important methods were deprecated because of potential deadlock they can create. Thread pool is an architectural concept where multiple threads form a worker pool that works together.
What is simple controller in JMeter?
Simple Controller helps in organizing and storing the Samplers and other Logic Controllers. It doesn’t offer any other functionality like other controllers. The Following Example Demonstrates the simple controller and Module controller: Open the JMeter and then add Thread Group to the Default Test Plan.
How do I run two thread groups in JMeter?
Resolution
- Combine the thread groups in a single JMX. All thread groups run concurrently unless specified differently in the test plan.
- Store the samplers of each JMX in one thread group in a single JMX under a Parallel Controller .
- Create a test for each JMX and combine them in a Blazemeter multi test.
Is Garbage Collector A daemon thread?
How GC works. Java Garbage Collector runs as a Daemon Thread (i.e. a low priority thread that runs in the background to provide services to user threads or perform JVM tasks).
What is Diamond thread?
Daemon thread in Java is a service provider thread that provides services to the user thread. Its life depend on the mercy of user threads i.e. when all the user threads dies, JVM terminates this thread automatically. There are many java daemon threads running automatically e.g. gc, finalizer etc.
What are the types of controllers in JMeter?
JMeter has two types of Controllers: Samplers and Logical Controllers. These drive the processing of a test. Samplers tell JMeter to send requests to a server. For example, add an HTTP Request Sampler if you want JMeter to send an HTTP request.
What is apdex in JMeter?
Apdex (Application Performance Index) is an open standard developed by an alliance of companies. It defines a standard method for reporting and comparing the performance of software applications in computing.
Can we start a thread twice?
No. After starting a thread, it can never be started again. If you does so, an IllegalThreadStateException is thrown. In such case, thread will run once but for second time, it will throw exception.
Is the main thread a daemon thread?
The main thread cannot be set as daemon thread. Because a thread can be set daemon before its running and as soon as the program starts the main thread starts running and hence cannot be set as daemon thread.
What is thread in Java with simple example?
A thread in Java is the direction or path that is taken while a program is being executed. Generally, all the programs have at least one thread, known as the main thread, that is provided by the JVM or Java Virtual Machine at the starting of the program’s execution.