I am new to Jmeter , actually I was trying to check the loading time taken for each page in my php application. I used highcharts API for the graphs. When clicking on data menu it will list out all the six graphs. I used Blazemeter chrome extension to record the loading time taken for the six graphs. Once loading time is recorded for each graphs i export the file with .jmx extension which is available in Blazemeter and imported in JMeter and started with iteration for one user, two users , five users and ten users. But when i was checking manually the second graph is taking more time for loading , approximately 7 Secs. But in my JMeter, loading time is shown as 0.534Secs for one user. Please anyone help me how to check the loading time for graphs.
with regards,
T.Ragith
This is most probably due to JavaScript-driven requests in your application, i.e. it uses AJAX technology.
As per JMeter project main page JMeter doesn't execute JavaScript found in the webpage, you need to either find a way to kick off the same requests real browsers do or switch to real browsers for your load testing via JMeter WebDriver Sampler.
Related
When I check the page loading time for a page in chrome Dev tool under network tab the system has taken 6 seconds
When I check the page loading time for a page in chrome Dev tool under performance tab the system has taken 8 seconds
When I check using jmeter by using blaze meter recorded file its taking 12 seconds..
Note: I have one main jsp request and 5 sub request....
Number of User:1
Ramp-up period:1
Loop count:1
I'm assuming you have kept embedded resources (such as png, img, gif, js files) in the script. If so, jmeter executes them in a sequence which increases response time. Try using retrieve embedded resources check box in HTTP request defaults and check parallel downloads. By default it's value is 6.
Most probably this is due to HTTP Caching, there are so called "embedded resources": images, scripts, styles, fonts, sounds, etc, if you visit the page in the browser not the first time - the chance that the embedded resources are not downloaded each time is very high.
JMeter always establishes "clean" session, so if you want to compare it's response time with browser response time you should set up "clean" session in the browser as well, i.e. tick "Disable cache" box in the browser developer tools
Check out How to make JMeter behave more like a real browser guide for more hints on how to properly configure JMeter for producing the same network footprint as real browsers do.
I need to perform load test on our web application that involves user interaction to the web pages. So i have written selenium scripts to
handle the click events.For,example we have functionalities like some users has to perform signup/registering to our site,some has to login and perform click actions and logout, and a set of users has to visit our home page, click on multiple URL links available on the home page.
In JMeter,i have added one threadgroup each for above mentioned functionalities.Each threadgroup has "JUnit Request Sampler" which calls the selenium methods that has code for performing click actions.
I have setup the "Thread Properties" for the threadgroups to run 200 threads per minute over a span of 5 to 10 mins[target is for 15 mins]
Default browser i am using is "Firefox".I have also set the JMeter properties such that i wouldn't landup into any memory issues.
I am running the scripts in non-gui mode and collecting the result into a jtl file.
The problem i am facing here is, while scripts are executing multiple browsers openup and as each page involves click events,some of the clicks are not happening correctly resulting in increase in error count. If i use very minimal number of threads with time delay then no errors are seen.
I have tried with distributed mode testing as well but there was no major reduce in error count.
I am looking forward for a solution or rather suggestions that can help me out to have minimal or zero errors while running JMeter scripts that involves user interactions and achieve intended load or thereafter increase the load.
Regards
Praveena
As per WebDriver Tutorial it is not recommended to use WebDriver to conduct the load onto the web application
From experience, the number of browser (threads) that the reader creates should be limited by the following formula:
C = B + 1
where C = Number of Cores of the host running the test
and N = Number of Browser (threads).
Looking into Firefox browser requirements I strongly doubt you have a computer with 200 cores and 400 GBs of RAM therefore my expectation is that you should use JMeter's HTTP Request samplers to create the load.
Browsers don't do any magic, they send HTTP Requests and render the responses, so well-behaved protocol-based JMeter tests will look just like a real browser for the application under test. So I would recommend converting your Selenium tests into "pure" JMeter tests, you can leave 1-2 browsers to measure end-user experience when the application is under the load.
I use JMeter for checking load testing.
I note a time with stopwatch when i check load time personally it was
8.5 seconds
when i run same case with JMeter it gave load time of 2 seconds
There is huge difference between them, How can i verify the actual time?
e.g : if one user taking 9 seconds to load the form while in JMeter it is given load time 2 seconds
Client time is a complex item, as you can see from the clip from the Chrome Developer tools, performance tab, above. There's lots going on at the client which does lead to a difference between the time you see with an HTTP protocol test tool, such as JMETER (and most of the other performance test tools on the planet) and the actual client render.
You can address this Delta in a number of ways:
Run a single GUI Virtual user. Name your timing records such as "Login" and "login_GUI." The delta between the two is your client weight. Make sure to run the GUI virtual user on a dedicated host to avoid resource contention
Run a test with all browsers. This was state of the art in 1995. Because of the resource cost and the skew imposed on trying to figure out the cost of the server response the entire industry shifted to protocol level virtual users. Some are trying to bring back this model as "state of the art." It is not
Ask a performance question earlier, also known as "shift left..." Every developer has these developer tools at their disposal, as does every functional tester. If you find that a client is slow for one user, be curious and use the developer tools to identify, "why?" If you are waiting to multi user performance testing to answer questions related to client weight, then you have waited too long and often will not have the time or resources to change the page architecture in meaningful ways to reduce the client page cost. This is where understanding earlier has tremendous advantages for making changes.
I picked the graphic above deliberately to illustrate the precise challenge you have. Notice, the loading of the components takes less than a tenth of a second. These are the requests that JMETER would be making. But the page takes almost five seconds to "render." Jmeter is not broken, it is working as designed. It is your understanding that needs to change on which tools can be used to pull particular stats for analysis.
You can't compare JMeter load time to browser as is, also because your browser will load JavaScript files and can call JavaScript functions on page load while JMeter doesn't execute JavaScript.
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).
Just a side note - you can use plugin to check exact load time in chrome.
Well-behaved JMeter test timing should be equal or similar to real user timing, if there is a 4x times difference - most probably your JMeter configuration is not correct.
Probably the most important. Make sure your HTTP Request samplers are configured to retrieve so called "embedded resources" (images, scripts, styles) which are referenced in the web page
If your application is using AJAX technology make sure you execute AJAX-driven requests as well and add their elapsed time to main sampler using i.e. Transaction Controller.
Make sure you mimic browser's:
Cookies via HTTP Cookie Manager
Headers via HTTP Header Manager
Cache via HTTP Cache Manager
Assuming all above you should be receiving similar to real user experience page load time. See How to make JMeter behave more like a real browser article for more detailed information on the above tips.
In addition to the answers provided by James and user7294900, please find these images to help you understand the reason behind the difference in time given by your stop watch and JMeter.
Below image gives the ideology behind how JMeter provides the time.
Below image gives the ideology behind how you have measured the time with
your stop watch.
Notice that there are additional actions performed by the browser when you are taking the time using your stop watch. This is the reason behind the huge difference in time between JMeter and your stop watch.
In addition to this, ensure that you are using the same test environmental conditions for both the tests (like same network conditions, same LG etc.)
Hope this helps!
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.
I'm trying to simulate a connection to a website. The goal of the simulation is to collect statistics on page loading time on browser side.
I configured JMeter Flagging the option Retrieve Embedded Resources in order to simulate the real time to load the whole page. The issue is that while from a real Browser i have a response time (let's assume for the page A the response time is 10 seconds) in JMeter I found i response time 20 times higher.
It seems JMeter takes a much longer time to gather embedded resources (e.g. js, images, ...)
Do you have any suggestion for this issue?
Kind Regards
Update 31/07
I discovered some resources are not completely downloaded. Using Firebug i see some components with 0 bytes downloaded that the browsere keep trying to download (but the user do not percieve since the page is loaded). Therefore i suspect JMeter keeps trying downloading it. Is there any chance to set a timeout to overcome this kind of situation?
Update_1 31/07
I figured out that the issue is related with nested iframes. setting httpsampler.max_frame_depth=0 i get the correct time. however i would like to understand the reason of this issue. Do I have to set other paramters?
Disable browser cache and re-run your test in browser.
Jmeter will not store cache, unless otherwise specified.
Hope this will help.
Add a HTTP Cache Manager to your test plan.
Real browsers retrieve images, scripts, styles, etc. but do it only once. In order to simulate browser behavior you need to configure JMeter appropriately.
See How to make JMeter behave more like a real browser guide for more test elements which can be used for this.