Quality is delighting customers
Check out Jmeter tutorial series here: http://www.softwaretestingclass.com/learn-jmeter-performance-testin...
Normally the process looks like:
See the following material for more information:
I would also recommend attending free JMeter Academy - most probably the best way of ramping up in JMeter as of now.
It depends on what your test is doing. If it's something long enough - it will be 20, if it's something very short - it'll be 1.
JMeter offers several options to control the load. In particular the most commonly used elemends are:
Synchronizing Timer - to pause threads unless certain number will be reached and fire them all at the same time.
Constant Throughput Timer - to specify exact load to generate, i.e. 20 requests per second.
Also JMeter concurrent threads are not "concurrent users" as real-life people do pauses between actions on web pages. If you don't set any pauses in your tests then 20 concurrent threads will stand for something like 200-250 concurrent users.
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