I would like to make Recovery testing to server, I can simulate connection pool full with high load and thus failed in timeout to get connection.
I need to start my test with high load, reach a failure and decrease load gradually,
JMeter can't change it dynamically so I search for plugins and Concurrency Thread Group is doing the opposite,
Increase it gradually, is there a way to make it decrease the value?
Is my only option is to start a new execution with decreased load?
Recovery testing is done in order to check how fast and better the application can recover after it has gone through any type of crash or hardware failure etc.
It can be done using vanilla JMeter without any plugins, JMeter acts as follows:
All threads defined in the Thread Group are started within specified ramp-up period (here you can gradually increase the load)
All threads start executing samplers upside down (or according to the Logic Controllers)
When thread doesn't have any samplers to execute and/or loops to iterate - it's being shut down.
So given you gradually start your requests and thread group is not configured to run forever - the ramp-down should be pretty much the same as ramp-up. You can "help" JMeter a little bit using Gaussian Random Timer, check out How to Ramp Down in JMeter guide for more details.
I found a jmeter plugin jp#gc - Ultimate Thread Group which I can start with high load by adding first row with high thread count and then decrease thread count by adding second (or more) row .
Related
I have a requirement to create simple Burst test in Jmeter:
10 requests-> 20 requests -> 30 requests
On single worker mode.
Throughput 20ms
Anticipated response time : <=200ms
How can we achieve this with Jmeter without using parallel threads?
I am looking for a simple solution.
Thanks a lot
Add plugin
Ultimate Thread Group to JMeter
Add Ultimate Thread Group component with settings of 3 rows
Set Start Threads Count 10,20 and 30
Use different start times so requests batch will be executed in different times
"Ultimate" means there will be no need in further Thread Group plugins. The features that everyone needed in JMeter and they finally available:
infinite number of schedule record
separate ramp-up time, shutdown time, flight time for each schedule record
and, of course, trustworthy load preview graph
Consider using Throughput Shaping Timer and Concurrency Thread Group combination which provides flexible way of defining load patterns:
They can be connected together using Feedback Function so JMeter will be able to kick off more threads in order to reach the desired throughput (number of requests per second) if current amount is not enough.
Both can be installed using JMeter Plugins Manager:
While understanding concept of Concurrent thread and ultimate thread group, i am confused to understand result of summary/aggregate report while running concurrent thread or ultimate thread group .For example if i have 200 user and ramp up time 60 sec then i didn't see all sampler request as 200 sample after completing execution successfully but only few sampler request have 200 sample. when i use normal thread group then i always got thread count same for each sampler request after completing execution .
for realistic load testing with more user , could you please suggest me which thread group should prefer.
Could you please provide valuable guidance with some valuable link/book and also share me standard performance bench mark criteria or key parameter detail while doing load testing.(if any bench load parameter value does not meet standard then we can say that there is a performance issue)
Thanks for giving valuable time in advance.
Thanks
amit
This is due to the fact that:
Your application response time is too high
Your test duration is too low
For example I can see response times > 80 seconds:
it means that if a single virtual user has cumulative response time for 2 samplers > 160 seconds and the test duration is 120 seconds it will not be able to execute all the requests. Just increase your test duration to be i.e. 10 minutes and you should see more virtual users capable of executing all the Samplers you defined in the test plan.
Also given first user is capable of executing all the requests successfully and in time it looks like that your application gets overloaded hence cannot respond fast enough when the number of concurrent users reaches some "critical threshold", you can add listeners like Active Threads Over Time and Response Times vs Threads, this way you will be able to correlate increasing load with the increasing response time.
If also makes sense to collect:
Baseline health metrics of your application (CPU, RAM, Network, Disk usage, etc.), it can be done using JMeter PerfMon Plugin.
Lower level details like slowest methods, largest objects, heaviest database queries, etc. This form of information can be obtained using profiling tools specific to your application programming language(s).
I have a test plan where I have to pick 100 users from a CSV file. If I give threads count as 500 and loop count as 1, then I can see 490 are failed and only 10 are passed. But at the same time, if I give threads as 5 and loop count as 100, all the tests are passed. Aren't these same where the total number of requests are 500?
Is this because 500 threads and 5 threads?
If you start 500 threads, By default, the file is only opened once, and each thread will use a different line from the file. However the order in which lines are passed to threads depends on the order in which you execute, which may vary between iterations.
Change Your Jmeter CSV-DataSet-Config property "Recycle on EOF - True"
; Your Issue will solve
Hope This Helps!
You get different results because you apply different load pattern. JMeter acts as follows:
Each Thread Group kicks off threads (virtual users) within the ramp-up period
Each Thread starts executing Samplers upside down (or according to the Logic Controllers)
When the thread doesn't have any more samplers to execute or loops to interate it is being shut down
So reasons could be in:
Your application isn't capable of handling 500 users. Checks its logs for error details. If there are no specific errors it might be lack of hardware resources, re-run your test with JMeter PerfMon Plugin Telemetry to check the impact of the increasing load onto hardware resources consumption
Your application underlying components is not suitable for high loads. Some application and database servers come with connection limitations, low memory allocation, etc. in other words configuration suitable for development and debugging. Production deployment assumes totally different configuration therefore it needs to be inspected and amended
Your JMeter instance cannot create the required load. Like in point 2 JMeter default configuration is good for tests development, however when it comes to running load tests you need to mind some important points:
Increase JVM Heap size for JMeter
Run your test in non-GUI mode
Disable all the listeners during test run
See Reducing resource requirements chapter of JMeter's User Manual for more information
I have entered 500 to be the number of thread group and ramp up time to be 120 seconds but when the report is generated,the virtual users count is only 15 or in composite graph-active threads over time is raised to near about 12. So I am bit confuse active threads counts. Because the data(threads) or numbers that I filled in test plan before test is different and after result is different. What about scaled values in graph?and x10?Something related to threads?
Each JMeter thread representing a virtual user after initialization starts executing samplers upside down (or according to the Logic Controllers).
If thread doesn't have more samplers to execute and no more loops to iterate it's being shut down. It looks just like your case. See Max Users is Lower than Expected article for more detailed explanation and workaround.
Usually people set Loop Count to "Forever" and use Runtime Controller to so test could finish in designed time. Another option is using i.e. Ultimate Thread Group available via JMeter Plugins which provides convenient way of defining a load scenario.
Hi I am new to JMeter and I do know how to perform load tests using JMeter. I tried to figure out how a stress test or a capacity test is performed via JMeter. Is it by gradually increasing threads in JMeter we can determine when performance hits are arise and get that threshold and run tests above the threshold. Does it make a stress test then?
Confused in how to perform a stress test and a capacity test with Jmeter tool.
JMeter is very flexible and load scenario can be established in multiple ways. Out of box there are following test elements available:
Thread Group - where you can set
Virtual Users Number
Ramp Up Time
Iterations count
JMeter acts as follows: each samplers are being executed upside down with each thread representing virtual user. When thread has no more samplers to execute and no more iterations it is being shut down. For ramp-up bit: by default settings JMeter tries to kick off all the threads as fast as it can but you can configure it to simulate increasing load. I.e. if you have 30 users and 30 seconds ramp-up time JMeter will start with 1 user and add one per second.
Constant Throughput Timer
Constant Throughput Timer can be used to set exact load in "Requests per minute".
Synchronizing Timer
Synchronizing Timer pauses test threads until threshold specified is reached. Once there are enough threads in pool JMeter releases them all at the same moment providing "spike" simultaneous load.
You can also use i.e. Ultimate Thread Group available via JMeter Plugins which provides easy and quick way of defining load scenario like:
Start with N users
Start up for S seconds
Hold the load for L seconds
Shut down test threads in T seconds
Hope this helps.
first of all both Load test & Stress test can help you determine the capacity of the system.
In order to perform load test, use the "Thread Group" available in Jmeter.
http://jmeter.apache.org/usermanual/test_plan.html
while doing a load test you will have to increase the user load gradually after 1 iteration has been executed completely e.g. you want to execute load test for 100, 200, 300, .... ,1000
so first iteration you have to keep "no. of threads" as 100, run the test save the results and then change the value in "no. of threads" to 200 & so on.
In order to perform stress test, use "jp#gc Stepping Thread Group"
http://testingfreak.com/tools/jmeter/stepping-thread-group/
hope this will help.