How to correctly configure number of requests in JMeter? - performance

My performance test strategy is to use JMeter to send 3 different requests to a linux server continually. They are Init, Calculate and Apply.
The number of active users of peak hour is 40 and the number of each request per hour is 200. The load test should be conducted with the peak usage with no less than one hour.
If my understanding is correct, running the test for two hours eventually there will be 1200 samples shown in the result table (200 requests * 3 * 2 hours). However, with the following configuration there are much more samples sent to the server.
Thread Group:
- Number of threads: 200
- Ramp-up time: 3600 seconds
- Duration: 7200 seconds
I have also tried setting the number of threads 50, the result is still far more than my expectation.
May I know how to configure the JMeter correctly ?

Your configuration should be:
Number of threads : 40
Ramp-up time: Should be short in your case, its value tells in how much time threads will go from 0 to 40.
Duration is ok
Finally, as you want 200 requests per hour, which would be 600 for the 3 ones, it would be 10 per minute, you need to use Constant Throughput Timer inside a Test Action:
Where Test Action is :

Related

Understanding difference between thread group properties

i've started distributed performance testing using jmeter. If i give scenario 1:
no.of threads: 10
ramp up period: 1
loop count: 300
Everything runs smooth, as scenario 1 translates to 3000 requests in 300 seconds. i.e. 10 requests per second.
If i give scenario 2:
no.of threads: 100
ramp up period: 10
loop count: 30
Afaik, scenario2 is also executing 3000 requests in 300 seconds, i.e. 10 requests per second.
But things started failing i.e. sever is facing heavy load and requests fail. In theory both scenario1 and scenario2 should be same, right? Am i missing something?
All of these are heavy calls, each one will take 1-2 seconds under normal load.
In ideal world for scenario 2 you would have 100 requests per second and the test would finish in 30 seconds.
The fact that in 2nd case you have the same execution time indicates that your application cannot process incoming requests faster than 10 per second.
Try increasing ramp-up time for 2nd scenario and look into the following charts:
Active Threads Over Time
Response Times Over Time
Transactions Per Second
Normally when you increase the load the number of "Transactions Per Second" should increase by the same factor and "Response Time" should remain the same. Once response time starts growing and number of transactions per second starts decreasing it means that you passed the saturation point and discovered the bottleneck. You should report the point of maximum performance and investigate the reasons of the first bottleneck
More information: What is the Relationship Between Users and Hits Per Second?
In scenario 2 after 10 seconds you have 100 concurrent users which execute requests in parallel, your server may not handle well or prevent such load
Concurrent user load testing sends simultaneous artificial traffic to a web application in order to stress the infrastructure and record system response times during periods of sustained heavy load.
In scenario 1 after 10 seconds you have 10 concurrent users looping through the flow, without causing a load on server
Notice your server may have restriction on number of users requesting only on specific request(s)
We shall be very clear about the Rampup time
Following is extract from the official documentation
Scenario 1 : no.of threads: 10
ramp up period: 1
loop count: 300
In the above scenario 10 threads(virtual users) are to be created in 1 seconds. Each user will loop 300 times. Hence there will be 3000 requests to the server. Throughput cannot be calculated in advance with above configuration. It fluctuates based on the server capability, network etc. You could control the throughput with some components and plugins.
Scenario 2 : no.of threads: 100
ramp up period: 10
loop count: 30
In scenario 2 100 threads (virtual users) are created in 10 seconds. 100 virtual users will send requests concurrently to the server. Each user will send 30 requests. In the second scenario you will have higher throughput (number of requests per seconds) as compared to the scenario 1. Looks like server cannot handle the 100 users sending requests concurrently.
Ramp up time is applicable for the first cycle of each thread. It will simulate delays between first request of each user in their first iteration.

Jmeter - Calculating Ramp-up period

I am trying to send 1100 requests per minute to my API endpoint for a period of 5 minutes, so in total, I will make 5500 requests to the endpoint.
Based on the above requirement, Here is how I have set up my Jmeter:
It seems like I have misconfigured Jmeter, because in the end I can see Jmeter has made 8401 requests to the API instead of 5500.
What have I missed in the configuration?
Does the "Infinite" check-box need to be checked or unchecked?
The number of requests you're expecting (which is 5500) for this test plan is wrong.
As per your expectation, I think, you are making confusion between the Threads and Requests.
Ramp up is the time in which all the users arrive on your tested application server.
Requests are simulated by samplers but threads are the simulation of users.
According to your test plan:
- Total Number of Threads: 1100 vitual users
- Ramp-up time: 60 (1 min)
- Loop count: Infinite
- Test duration: 300 sec (5 min)
- No of requests/sampler in Test Plan: Unknown, assuming it 1
JMeter Execution:
JMeter will kick off those 1100 virtual users in 60 seconds according to the ramp-up time. So, (1100/60)~ 18 users will be active in every second for the first minute of your test. Each thread/user will execute the requests or samplers you have defined in your test plan hierarchy. As you have defined the loop count to infinite, each thread will execute the requests repeatedly until the test finishes. After 60 seconds, all of your 1100 users will be actively hitting those samplers/requests for the remaining 4 mins.
So the total number of requests you will be able to make through JMeter depends on your application response time.
If the avg response time of your requests is 1 second (assuming you have only 1 requests in your test plan), then you will be able to hit total 264000 (264000/240 = 1100 requests per second) for the last 4 mins (when all of your 1100 users are active) of your tests. You can also verify this accordingly by using Active Threads Over Time and Hits Per Second listeners.
So, Please double check the avg response time of your application or the requests/samplers you are using in your test plan.
If you want to control JMeter's throughput to 1100 per minute, you can use a Constant Throughput Timer at your test plan level and use target throughput value as 1100.
Do not forget to add the count of ramp-down time in your test duration. Yes, when you ramp up i.e. in the first minute generally you get more requests as threads are starting. In your case, your test duration should be 7 mins (60 seconds for the ramp-up 1100 users + 300 seconds for 5500 requests + 60 seconds for the ramp down for 1100 users).
You can also check this thread for more : How should I calculate Ramp-up time in Jmeter.
Please note- The total number of requests is related to throughput, Whereas the number of active threads performing the same activity is related to concurrency.
I am trying to send 1100 requests per minutes to my API endpoint for a period of 5 minutes, so in total I will make 5500 requests to the endpoint.
I don't know how you came with this 5500 number but this is not very correct.
Your setup means that:
JMeter will add 18 virtual users each second for 60 seconds
After 60 seconds pass JMeter will run 1100 users for another 4 minutes
The total number of requests JMeter will be able to make will mostly depend on application response time.
If you want to limit JMeter's throughput to 1100 requests per minute consider using Constant Throughput Timer or Precise Throughput Timer
If you don't want to limit JMeter's throughput but want 5500 executions either:
Set "Loop Count" to 5 (but in that case you might fail to get 1100 concurrent users)
Or use Throughput Controller in Total Executions mode so JMeter would stop after executing 5500 requests

JMeter - Cannot reach 15 000 requests in 5 minutes even though server is capable of it

I have a problem with JMeter that I can't figure out.
I have 3 requests in one thread group. Each request needs to be executed 5000 times in 5 minutes which means I need to execute 15 000 requests in 5 minutes altogether.
The thread group is set up like this:
Number of threads (users): 50
Ramp-up period: 1
Loop count: forever
Duration (seconds): 300
Each request has a Constant throughput Timer:
Target throughput: 1000.0
Calculate Throughput based on: all active threads in current thread group
And the results after the test run is complete are around 2000-3000 requests and that is too low. I can't figure out which settings are wrong.
Tests are ran in non-GUI mode on an Azure virtual machine with a Intel Xeon E5-2673 #2.3 GHz with 16 cores and 32gb of RAM and the server is more than capable of executing more requests since the response time is about 1 second so hardware should not pose a problem. JMeter heap memory is set to 12 GB.
Any help is appreciated!
I have 3 requests in one thread group. Each request needs to be executed 5000 times in 5 minutes which means I need to execute 15 000 requests in 5 minutes altogether.
That means you have to execute thread group for 5000 times in 5 mins => 300 seconds. If you execute thread group that much of time, you will automatically generate 15k requests.
From Documentation:-
Loop Count Number of times to perform the test case. Alternatively, "forever" can be selected causing the test to run until manually stopped.
When you set loop count: forever or any value in loop count for that matter, it means you want next set of users(threads) [which you have defined as 50 now], only when you are done with the first set 50 users request (150 requests as each thread group as 3 requests). Now, this 50 users request may take unexpected time and your next set will be returned only after this 50 users are done.
So to solve the problem at hand, you should have the following configuration for the thread group :
Number of threads (users): 5000
Ramp-up period: 300
Loop count: 1
So this means after every second around 17 Threads would be on-boarded.
To achieve your desired value configure the following
Number of threads (users): 50 / 60
Ramp-up period: 30
Loop count: forever
Duration (seconds): 300
It is good practice to give some ramp up time.
Also Constant Throughput Timer works on minute level and your desired throughput should be
Target throughput (in minutes): 3000.0
Calculate Throughput based on: all active threads in current thread group
So now, in 1 minute, JMeter will try to send 3000 requests and in 5 minutes, request count will be more or less around 15000.
Here are a few recommendations to tackle tests like this:
Use Ultimate Thread Group to create the threads required to run your tests.
Increase the total number of threads to 150-200 - Depending on the response time of your requests, 50 threads may be busy and you are not able to scale beyond certain throughput.
Add throughput shaping timer under Ultimate thread group, to maintain the throughput of 50RPS for 5 minutes(300 Seconds).
The combination of Ultimate Thread Group and Throughput Shaping Timer will allow you to have granular control over your requests and RPS you want to achieve.
Set Ulitmate Thread Group and Throughput Shaping Timer as below.
Put all your requests below Throughput Shaping Timer and you should be able to achieve the expected load.
Try to use Stepping thread group. It will allow you to send 50 user per second upto 300 second.
Download jar from below link.
https://jmeter-plugins.org/wiki/SteppingThreadGroup/

How do I achieve the expected throughput in JMeter for a given scenario?

I have about 300 users (configured in the thread group) who would perform an activity (e.g.: run an e-learning course) twice. That would mean I need to expect about 600 iterations i.e 300 users performing an activity twice.
My thread group contains the following transaction controllers:
Login
Dashboard
Launch Course
Complete Course
Logout
As I need 600 iterations per 5400 seconds i.e 3600 + 900 + 900 seconds (1 hour steady state + 15 mins ramp-up and 15 mins ramp-down), and the sum of sampler requests within the total thread group are 18, would I be correct to say I need about 2 RPS?
Total number of iterations * number of requests per iteration = Total number of requests
600 * 18 = 10800
Total number of requests / Total test duration in seconds = Requests per second
10800 / 5400 = 2
Are my calculations correct?
In addition, what is the best approach to achieve the expected throughput?
Your calculation looks more or less correct. If you need to limit your test throughput to 2 RPS you can do it using Constant Throughput Timer or Throughput Shaping Timer.
However 2 RPS is nothing more than statistical noise, my expectation is that you need much higher load to really test your application performance, i.e.
Simulate the anticipated number of users for a short period. Don't care about iterations, just let your test to run i.e. for an hour with the number of users you expect. This is called load testing
Do the same but for longer period of time (i.e. overnight or weekend). This is called soak testing.
Gradually increase the number of users until you will see errors or response time will start exceeding acceptable thresholds. This is called stress testing.

Run http sample in Jmeter for 1 minute and generate only 200 requests

Please help me to achieve this type of load testing in Jmeter,i have configured Scheduler configuration but it is not running as per Duration as 60 minutes with in 10 seconds it is completing the requests and my Vusers -5 and Loop Count-50
Please help how to prepare this type of scenarios.
If you need 200 requests - decrease loops count to 40 (5 users x 40 loops == 200 total requests)
Also consider using Constant Throughput Timer or Throughput Shaping Timer to limit the throughput to 200 requests per minute (something like 3.3 requests per second).

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