Unable to reach the requested number of requests while running jmeter distributed - jmeter

I am working with 1 master, 50 slaves. Number of threads: 20
I have 1 thread and there are 3 samples in it. I'm starting the tests, but as a result of the test, I see that you are going 500-700 requests.
1000 requests from each should go. But it doesn't go.

You have 20*50=1000 threads in total.
You can reach 1000 requests per second only if response time is 1 second sharp.
If response time will be 0.5 seconds - you will get 2000 requests per second
If response time will be 2 seconds - you will get 500 requests per second.
If you need to simulate X requests per second you need to add more threads (or alternatively go for Concurrency Thread Group and Throughput Shaping Timer combination)
But remember that the application under test must be able to respond fast enough because if it doesn't - any JMeter tweaks won't make any difference.
By the way, 1000 requests can be simulated from a modern mid-range laptop without any issues (unless your requests are "very heavy"), just make sure to follow JMeter Best Practices

Related

jmeter thread group vs Constant Throughput Timer

I am conducting a performance test (TPS) using jmeter.
I am requesting about 10,000 TPS, but the following two results are different.
(Position that 10,000 TPS responds normally)
1000 thread x 600 target throughput(in samples per minute)
100 thread x 6000 target throughput(in samples per minute)
I think the two results should be the same, but why is the response time delayed as the thread increases?
I think the two results should be the same - why they would be the same?
Let's imagine your system has fixed response time of 1 second, in that case:
With 1000 threads you will get 1000 requests per second and you can limit the throughput to 10 requests per second using the Constant Throughput Timer
With 100 threads you will get 100 requests per second, no limiting is required
And what if response time is 2 seconds?
With 1000 threads you will get 500 requests per second
With 100 threads you will get 50 requests per second
Constant Throughput Timer:
acts precise enough on "minute" scale, if your test lasts less than minute it might not apply the throughput
can only pause the threads to limit the throughput (requests per minute) to the desired value. If current number of threads is not enough in order to conduct the required load - the time won't have any effect.
If you want to send requests at the rate of 10000 TPS it worth considering going for the Throughput Shaping Timer and Concurrency Thread Group combination connected via the Feedback Function in this case JMeter will be able to kick off extra threads if current number is not sufficient.
But also be informed that:
JMeter should be able to start as many threads as needed to send 10000 TPS so make sure to follow JMeter Best Practices or even consider going for Distributed Testing Mode
Application needs to be able to handle the load and respond fast enough, JMeter waits for the previous response before starting the new request so if application is able to serve i.e. 5000 requests per second only you won't be able to reach 10000 by any means

Apache JMeter Constant Throughput Timer not increasing number of Requests per Second

In my test plan , I only have one Thread Group.
Thread Group Screenshot
I have CSV file with 10 users and 15 API requests in Loop Controller.
Loop Controller Screenshot
All of my requests are passing, An average of 55 requests/second were being sent but I want to know the maximum capacity of the server.I need to sent 150 requests per second, So I added Constant Throughput Timer with Target Throughput 9000 Constant Throughput Timer Screenshot .But it is still sending an average of 55 requests/ second. Here is the screenshot of command line run output. Output
Can anyone help me understand what I am doing wrong here ? Which values should I change in order to acheive 150 requests per second ?
JMeter sends request, WAIT for answer, send another request
If you add timer, it basically add some sleep to this -> you can't increase throughput, only decrease. Check manual https://jmeter.apache.org/usermanual/component_reference.html#Constant_Throughput_Timer
You should check your server - Load, CPU, Memory, IOs - disks, network ...
Check your JMeter machine as well
Are the answers from server alright? Do you check e.g. HTTP 200 OK?
You can try add more ramp up time, inscrease/decrease user count, but first check your server!
You're trying to reach 150 requests per second with each thread, you need to amend at least this bit:
You're trying to reach 150 requests per second with 10 users which means that each user needs to execute 15 requests per second. It's only possible if response time of your application is 66 milliseconds or less and the average response time of your application is around 200 milliseconds so it explains the actual result
JMeter's Constant Throughput Timer can only pause the threads in order to limit requests execution rate to the desired value, it won't kick off extra threads if current amount is not sufficient.
So the options are in:
Increase the number of threads in the Thread Group to i.e. 50 (you may need even more)
Or consider switching to Throughput Shaping Timer and Concurrency Thread Group combination, the Throughput Shaping Timer is more "precise" and it can be connected to the Concurrency Thread Group via Feedback Function so you will be able to kick off more threads to reach and maintain the desired throughput

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.

Need to 2350 users per second in Jmeter

I have a task to load test on application which needs to respond 2350 users per second. For that I have set us something like this in Jmeter:
I have added a Thread group. In that I have set:
Number of threads(users): 2350
Ramp-up period: 1 Second
Loop Count: 1
Will it solve my purpose to load test of application with 2350 users??
It will. But only if response time for each virtual user will be equal 1 second.
There are 2 common load patterns, for implementing both you will need Timers
Actually it might be the case you don't need as much as 2350 thread to simulate 2350 users as real life users don't hammer the server non-stop, they need some time to think between requests. Besides page loading time also needs to be considered.
Let's imagine you have 2350 users. Each user performs an action each 15 seconds. Page loading time is 5 seconds. So each user will be able to hit the server 3 times per minute. So 2350 users will produce 7050 requests in minute which stands for 117.5 requests per second only. If this is what you're looking for consider adding Constant Timer or Uniform Random Timer
If you need to simulate 2350 requests per second, not users, you need to handle it a little bit differently. There are 2 Timers which are designed to set exact "throughput" - a number of requests per time unit. They are:
Constant Throughput Timer
Throughput Shaping Timer - an advanced version of the Constant Throughput Timer, available via JMeter Plugins project.
Remember that above timers can only pause the threads, they won't kick off new virtual users if you don't provide enough on Thread Group level so make sure you have at least as much as you try to simulate, or it's better to have 2x more in your virtual pocket just in case. Also check out JMeter tuning tips from 9 Easy Solutions for a JMeter Load Test “Out of Memory” Failure as JMeter default configuration isn't something you can use to create such a load.
The setup you described just creates 2350 parallel users (2350 separate connections), but doesn't guarantee that every thread will be completed exactly in 1 second. Ramp-up period - how fast all threads will start to send requests. So, in the case you described Jmeter will do the following:
Create 2350 separate threads.
The difference between 1st and last thread start will be 1 second (approximately).
Every thread will be implemented only once (loop count).
For real scenarios when you need specific throughput for continuous period of time it's better to use Constant Throughput Timer. It controls the amount of requests sent by thread(s) and changes delay between requests when it's necessary to meet the value you defined. So, your real throughput doesn't really depend on the total amount of threads (users). Sometimes less users can send requests faster (depends on your application).
To control your throughput while running, just add Summary Report to your test plan.
Moreover, for this specific scenario (2350 users) it can be potentially difficult to generate so many requests in 1 second. In this case, you need to use distributed load with some Jmeter slaves and 1 master.

Simultaneous SOAP Requests with JMeter

We have test-plan like below:
Test Plan
Thread Group
SOAP/XML-RPC Request 1
SOAP/XML-RPC Request 2
SOAP/XML-RPC Request 3
We have an issue when our service goes down on a certain day with a large load. We want to load test requests/responses per second, ranging from 500 to 10,000 requests over 20 mins to 1 hour.
Setting the thread value to 1200 for example only gives us roughly 60 per second. Any help to get this value up would be great folks.
ranging from 500 to 10,000 requests over 20 mins to 1 hour.
Do you mean 500 to 10,000 requests per second, or for example 10,000 requests over 30 mins which are a little over 5 requests på second?
I you are starting 1200 threads and not getting more than 60 requests per second it is probably not JMeter limiting the throughput. If you are sure the system can manage a higher troughput (thus it is not a service hardware problem) then I would check the network capacity between the load generating server and the service for bottlenecks.

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