I am trying to measure bandwidth utilization of a site using WireShark by simultaneously logging in 25 users and performing various activites on site in JMeter
I have recorded a script in JMeter to login and perform activites. But when I perform same activities for 1 user, in Browser and JMeter, I am getting different bandwidth utilization.
Expected result = Bandwidth should be same when same activites are performed in Browser and JMeter for 1 user.
Actual Result = I am getting Avg. 32k bytes/sec in Browser and Avg. 430k bytes.sec in JMeter
The reason behind this is already in the Jmeter Documentation
JMeter is not a browser, it works at protocol level. As far as web-services and remote services are concerned, JMeter looks like a browser (or rather, multiple browsers); however JMeter does not perform all the actions supported by browsers. In particular, JMeter does not execute the Javascript found in HTML pages. Nor does it render the HTML pages as a browser does.
Related
For performance testing testing Jmeter UI - endpoint - response time deferring from developer tool loading time
Ex Jmeter - endpoint response time is 615 Ms where in developer tool shows (Load: 13.30 s) Finish: 18.98 s
Note : Jmeter capturing 35 backend call/ Developer tool capturing 104 backend call
why jmeter couldn't capture all developer tool backend calls?
why jmeter couldn't capture all developer tool backend calls? do we have any solution for this issue
As per JMeter project main page:
JMeter is not a browser, it works at protocol level. As far as web-services and remote services are concerned, JMeter looks like a browser (or rather, multiple browsers); however JMeter does not perform all the actions supported by browsers. In particular, JMeter does not execute the Javascript found in HTML pages. Nor does it render the HTML pages as a browser does (it's possible to view the response as HTML etc., but the timings are not included in any samples, and only one sample in one thread is ever displayed at a time).
So apart from configuring JMeter to behave like a real browser when it comes to handling embedded resources, cookies, think times and so on you need to pay attention to the nature of the requests which are being called when you open the page in the browser.
If the request is created by JavaScript, i.e. it's an AJAX call JMeter won't make the request automatically when you open the page. However you can record it using JMeter's HTTP(S) Test Script Recorder and run after the main request. The cumulative response time can be measured using Transaction Controller
Check the Retrieve All Embeded Resources in Advanced tab of the http sampler and see what is the difference.
Times will be always slightly different between dev tools and Jmeter or between JMeter and other performance tools like Gatling for example.
I am new to performance testing. I have a task on measuring the web application performance. I need to find out which modules/calls are causing deadlock, timeout and memory issues.
Q1. How can I use JMeter to find out deadlock, memory and timeout issues? If I do the following steps, it is the right way to trace those issues?
create a test plan in JMeter, which contains multiple Thread Group.
In each thread group, it contains multiple HTTP requests and 200 or
more users plus infinite loop.
Monitor JMeter results and SQL
profiler for deadlock.
Q2. JMeter is the right tool for tracking those issues? Or, should I use browser based performance testing tool such as LoadNinja, LoadView?
Thanks
Bonnie
Q1 JMeter per se doesn't provide any toolchain to detect deadlock and memory issues, the HTTP Request sampler (or even better HTTP Request Defaults) provides possibility to set the timeouts, if the value is blank - it will default to operating system timeout or web server timeout, whatever comes the first
If you conduct some form of stress test, i.e. start with 1 virtual user and gradually increase the load at some point you will see that response time starts growing and number of requests per second starts decreasing. So it's the point of maximum system performance and after that the performance will be degrading.
To monitor application under test memory you can use JMeter PerfMon Plugin, it will allow you to state whether the lack of RAM is the cause of the performance issue
With regards to deadlocks, it should result in HTTP Request sampler failure (or timeout), JMeter won't give you the underlying reason, but it will give you the timestamp and you should be able to check what happened with your application/database at that moment.
Q2 well-behaved JMeter test must produce the same network footprint as a real browser, if your test plan is good enough the system under test shouldn't be able to distinguish whether it's being hit by JMeter or by a real user using the real browser. JMeter will not give you client-side performance metrics like page rendering time or JavaScript execution time as:
JMeter is not a browser, it works at protocol level. As far as web-services and remote services are concerned, JMeter looks like a browser (or rather, multiple browsers); however JMeter does not perform all the actions supported by browsers. In particular, JMeter does not execute the Javascript found in HTML pages. Nor does it render the HTML pages as a browser does (it's possible to view the response as HTML etc., but the timings are not included in any samples, and only one sample in one thread is ever displayed at a time).
how can we find rendering time from using values such as Latency, Connect time, Elapsed Time, Idle Time available to us in jtl file generated at end of test?
Is the below approach correct?
Rendering Time = Elapsed Time - Connect Time - Latency
This way (excluding network transport metrics) you will be able to get server response time, however as per JMeter project main page
JMeter is not a browser, it works at protocol level. As far as web-services and remote services are concerned, JMeter looks like a browser (or rather, multiple browsers); however JMeter does not perform all the actions supported by browsers. In particular, JMeter does not execute the Javascript found in HTML pages. Nor does it render the HTML pages as a browser does (it's possible to view the response as HTML etc., but the timings are not included in any samples, and only one sample in one thread is ever displayed at a time).
So JMeter will not actually load DOM, execute scripts, and display the generated page, it just sends a request, receives "plain" response and measures time in-between.
If you need to measure page rendering page while your application is under the load I would recommend going for WebDriver Sampler which provides JMeter integration with Selenium browser automation framework. This way you will be able to measure real user experience and you will have a possibility to use Navigation Timing API to get some extra information regarding page loading events and their duration.
How can we capture the end user response time in JMeter?
If there is any plug-ins available?
Can u please help me.
As per the main page of the Apache JMeter project
JMeter is not a browser, it works at protocol level. As far as web-services and remote services are concerned, JMeter looks like a browser (or rather, multiple browsers); however JMeter does not perform all the actions supported by browsers. In particular, JMeter does not execute the Javascript found in HTML pages. Nor does it render the HTML pages as a browser does (it's possible to view the response as HTML etc., but the timings are not included in any samples, and only one sample in one thread is ever displayed at a time)
Well-behaved JMeter test acts quite similarly to read users using real browsers given you properly handle embedded resources, cookies, headers, cache, AJAX calls, etc. See How To Make JMeter Behave More Like A Real Browser article for JMeter tuning recommendations.
I would also recommend using i.e. YSlow or WebDriver Sampler to measure real life user experience while the main load is being conducted using JMeter, this way you will be able to get more precise picture.
We are using Apache JMeter for the performance testing of web application. Apparently response time is too high in comparison to loading page in browser during load. When we open the page during load it opens in 2 seconds however JMeter reports 70 seconds. I understand browser memory cache and disk cache are used in browser however isn't JMeter cache manager does same. How to assert it, comparing response header is one option. Any thoughts on this will be appreciated.
It may be wrong configuration in the script. There won't be much difference between web browser and Jmeter response times (browser rendering time is ignored in Jmeter, not a big factor but must be considered)
If you are using single Http Sampler for a web page and retrieving all resources in tha page, then select "Parallel Downloads" option to '6' in Http sampler advanced section. So, you are simulating the browser behaviour of parallel downloading of the resources like .js, .css, images etc.
If you recorded the script using Test Script Recorder, then there will be an Http Sampler for each resource requet for that page which will be sent sequentially, hence increase in response time. You might be in this case, as of now, there is no feature/option to send the http samplers in parallel. so I suggest using the approach of adding one sampler, use parallel download of resources option in Http Sampler advanced section.
Also, caching is an important factor which decides the response time. Adding Http Cache manager can solve the issue in jmeter. This simulates browser behaviour of caching. I don't think there will be huge difference b/w browser and jmeter in implementing caching althought may not be perfect.
The reason could be the lack of resources on JMeter machine or JMeter not being properly configured for producing high loads. JMeter default configuration is good for load tests development and debugging, you can run load tests up to certain amount of virtual users, but if you need to conduct a really high loads - you need to perform some configuration changes.
First of all, double check my guess using jvisualvm and your operating system monitoring tools (there is PerfMon JMeter Plugin which can be used for monitoring different metrics on application under test and JMeter load generators sides). If it is the case - take the next steps to get the most performance of your JMeter installation:
Increase JVM Heap Size, NewSize, switch to ConcurrentMarkSweep Garbage Collector.
Run your test in non-GUI mode.
Disable all the listeners during the test.
Follow other recommendations from 9 Easy Solutions for a JMeter Load Test “Out of Memory” Failure article.