I want to start testing my JMeter scripts on my website using selenium,
If I follow the tutorial it state that it works only using 1 thread
DO NOT change the "Thread Group" values. They must all be set to 1.
Do I have a limit of running selenium test using 1 user per computer at a time?
I found also answers about selenium that it can be done, but not recommended. just want to make sure it shouldn't be done and keep executing 1 thread in JMeter + Selenium test.
Looking into Web Driver Tutorial:
Note: It is NOT the intention of this project to replace the HTTP Samplers included in JMeter. Rather it is meant to compliment them by measuring the end user load time.
So it is recommended to create the main load using JMeter's HTTP Request samplers and use one (or several) WebDriver Samplers to measure scripts execution time, rendering speed, etc.
Also pay attention to the quote from the 10 Minute Guide
Each browser consumes a significant amount of resources, and a limit should be placed on how many browsers the reader should create.
From experience, the number of browser (threads) that the reader creates should be limited by the following formula:
C = N + 1
where C = Number of Cores of the host running the test
and N = Number of Browser (threads)
eg, if the current reader's host has 4 cores, the formula would yield:
4 = 3 + 1
meaning that the script should have a MAXIMUM of 3 threads.
Also check out the memory footprint for a single browser accessing your application.
So theoretically you can kick off one browser per each CPU core after 1st and allocate around 1 GB of RAM for your browser (this may vary depending on how "heavy" your page is.
Check out The WebDriver Sampler: Your Top 10 Questions Answered for more details on Selenium and JMeter integration.
Related
I have a few question to clarify on my understanding of how JMeter works.
a. Thread Group determine the number of users but it does not determine how many HTML requests are generated per sec ? By default, I notice that every user will send a HTML request at a rate of 2 RPS.
b. If I want to change the RPS per user, then I need to use the Through Put Timer. But the Timer can only lower the request rate from 2 RPS to a lower number. It does not increase the RPS.
c. In order to increase the RPS, I need to add more Threads.
d. Does this mean we are limited to 2 RPS per user ? I see some website have links to many other websites so a webpage refresh would make many requests.
Is this the way JMeter works ?
I have a load test which has 8 transaction (eg CRUD,...). I intend to create a overall Test Plan and I want to use INCLUDE to add all the 8 txn. Do I just record the website and INCLUDE ? What should I include, only the HTML requests ?
I'm also thinking of adding Think Time and Add Variables in the 8 scripts before I INCLUDE.
Do I add the Config Element (eg CSV Dataset Config) in the 8 scripts or the overall Test Plan ?
Thanks.
By default each JMeter thread (virtual user) executes requests as fast as it can. If you want to slow JMeter down to mimic a real user which doesn't hammer the server non-stop and needs some time to "think" between operations - use Timers. More information: How do I Correlate the Number of (Concurrent) Users with Hits Per Second
If you want more RPS - add more threads (assuming that the system under test can give you more RPS)
You should INCLUDE everything which is related to your website (images, scripts, styles, fonts, sounds, etc.) but in the same manner as your browser does, i.e. don't record these requests and instead configure JMeter to download embedded resources and use HTTP Cache Manager so JMeter would request these resources just like browser does. Any requests to "external" websites should be excluded (unless they're also developed and supported and in scope for testing)
That's a good approach, if you use a value more than once it makes sense to declare it via User Defined Variables so you would be able to amend the value only in one place
You add it according to your scenarios, be informed about JMeter Scoping Rules
I want to run basic load testing scenario on a mendix application.
The initial requirement is at least 10 users should be able to perform some activities like login , file upload concurrently.
I have used the webdriver sampler in Jmeter with selenium and written the JS script for the actions.
The issue is it launches 10 browser on the same machine.
Please suggest the proper way to handle this. Currently it seems that the errors which I am getting are because of I am running the test on my laptop instead of distributed setup.
Also the total script takes 60 seconds to finish for single user. What should be the ramp up time?
If not Jmeter, please suggest any other suitable tool for this scenario.
As per The WebDriver Sampler: Your Top 10 Questions Answered article
Q. How do I Allocate the WebDriver Sampler?
A. First of all, don’t use the WebDriver Sampler to create the load! You’ll need around 1 CPU core per virtual user to keep the JMeter resource consumption within an acceptable range. The WebDriver Sampler should be used in addition to HTTP Request Samplers. Here’s an example of how it should be used:
1,000 of users are simulated by HTTP Request Samplers
1 user is the WebDriver Sampler
You should use the WebDriver Sampler to evaluate a real-life user experience. It’s most commonly used to measure the load times of pages when the system is experiencing high loads. The HTTP Request doesn’t really “render” the page and it can’t execute JavaScript. That’s why the WebDriver Sampler is so valuable - JMeter isn’t a browser and it overcomes limitations posed by this fact.
So first of all I would recommend re-considering your approach and migrating to HTTP Request samplers, you might be able to execute 10 browsers but if you will need to scale your test to 100 or 1000 users you will definitely won't be able to use this "real browser" approach while HTTP Request samplers act on HTTP protocol level, given you properly configure JMeter it will be no difference for the application under test whether the requests are originating from JMeter or from the real browser and the resources footprint will be much less.
With regards to the ramp-up time: the overall idea is to increase the load gradually so you could correlate the changing number of virtual users with changing metrics like response time, throughput, etc. According to JMeter Documentation:
The ramp-up period tells JMeter how long to take to "ramp-up" to the full number of threads chosen. If 10 threads are used, and the ramp-up period is 100 seconds, then JMeter will take 100 seconds to get all 10 threads up and running. Each thread will start 10 (100/10) seconds after the previous thread was begun. If there are 30 threads and a ramp-up period of 120 seconds, then each successive thread will be delayed by 4 seconds.
Ramp-up needs to be long enough to avoid too large a work-load at the start of a test, and short enough that the last threads start running before the first ones finish (unless one wants that to happen).
Start with Ramp-up = number of threads and adjust up or down as needed.
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 am new to jmeter and scripted for login authentication. Project requirement is to see the load for 10K concurrent users.
Script is working fine but to enhance I need suggestions on how to do the following thigs:
How can I see that how much time/average time the server takes to load a page.
which thread grp (studied Ultimate thread group but it is not very clear to me), should be used to see the maximum load the server can sustain in a particular time, for that rampup time need to be adjusted (correct me if I am wrong).
Please tell how to adjust the rampup time with respect to users/waiting time etc., in short how to do incremental/proportional observation to see the server performance(there is no Gateway error etc)
If you're looking for your server capacity boundaries I would rather stick to "requests per second" rather than to "concurrent users" as users may work with different applications in a different way.
For instance, if it is image gallery - the majority of users will be browsing images and do this rather frequently, for instance request next image i.e. each 2 seconds. Given image load time 1 second it will be an image per 3 seconds - 20 images per minute. In this case 10000 users will create the load of 3333 requests per second.
If your site is articles collection, users will need some more time to read an article, i.e. 2 minutes. In that case 10000 users will create 83 requests per second load.
JMeter provides Constant Throughput Timer out of the box, you can set desired target throughput in requests per minute using it. And once you're already aware of JMeter Plugins project, it offers Throughput Shaping Timer - more advanced test element with extended functionality.
If you go "throughput" way, no matter which Thread Group you choose as the load will be orchestrated by aforementioned timers.
See What is the Relationship Between Users and Hits Per Second? article for more detailed explanation.
Once you design your test scenario run it in non-GUI mode (as JMeter's GUI is very resource intensive) as:
jmeter -n -t /path/to/your/testplan.jmx -l /path/to/resultsfile.jtl.
When the test finishes, open JMeter GUI, add Aggregate Report listener and inspect min/max/average response times per requests.
I have made some PHP scripts and I want to test the response time for simultaneous users in JMeter. This scripts are run in a very short time (50 miliseconds).
What I would like to do is to simulate a load test from 1 to 50 of users where each user (thread) repeats the request for an unlimited period. So first we will have 1 user, after 2 simultaneous users, after 3 ... and so on.
I am trying to do it but with I have is response times where it is evident that there is no simultaneous request.
With HP loaddrunner we can define number of iterations for each thread, is this possible in JMeter?
You can possibly use these 2 thread group implementations
Stepping Thread Group
Ultimate Thread Group
from Jmeter Plugins package, that let you set load-increase for you scenario as you want.
As well you can also look onto Synchronizing Timer if you want "better" concurrency - but this is rather stress-testcase than load one.