Whether the each sample of jmeter will use or increase data usage?, Is there any solution available.
So as I understand, your problem is that while doing load tests whole day you have exceeded your network data limit and you want to know if there any ways to minimize the data usage.
Well, you can definitely minimize the data usage. But that is only possible by removing the samplers/requests. 10 GB is a lot of data and it seems that you are also performing static content requests in your JMeter scripts. So, you can remove these requests to reduce data usage.
But before doing so, you should ask the question if this approach is fine for your scenario. Normally, if we want to mimic real-time scenario then we include static requests. But if our load tests are to identify issues in specific area only then we can exclude static content requests.
Please check below question for further thoughts on this topic include static resources like images, css, js etc in tests
Consider the following:
Real browsers download embedded resources like images, styles, scripts, etc. But they do it only once, on subsequent requests the resources are being returned from the browser's cache. Add HTTP Cache Manager to your test plan to replicate this behaviour in your JMeter test
Focus solely on your application. If it uses content from 3rd-party websites - you don't need to include it into JMeter test as you don't have control of external websites content and won't be able to do anything if it becomes unavailable or will be loading slowly. So use "Embedded URLs must match" input of the HTTP Request Defaults to limit JMeter's scope to your domain(s) only. See Excluding Domains from the Load Test guide for more details.
Related
I have been using Jmeter for performance testing my web application. I have recorded the jmeter script by excluding js,css and other static content files.
While running the script, Jmeter doesnt execute javascript files so ajax XHR request are not sent. To overcome this i have recorded the script with js, css and other static content and it recorded all the Ajax xhr request too. But the performance results seems to be different from the browser loading time. Also i need to use cache during my performance testing.
Below is how my test plan will look like,
Included Retrieve all embedded resources in HTTP Request manager.
Concurrent pool size is 6
I have added HTTP cookie manager and Cache manager.
I have added a loop controller (This is for caching, jmeter will cache the files on first iteration and it will use the cached files
after that)
The problem i am facing is that the time taken for rest call are double the time shown in the browser console for single user. I have tried all other combinations but always i am getting higher time than the browser console.
I have tried to use the Selenium webdriver plugin to simulate the browser behavior but it doesnt seems to be using the cache. (https://www.blazemeter.com/blog/how-load-test-ajaxxhr-enabled-sites-jmeter)
Is there any other way to solve this problem? I want to take the metrics with cache so kindly suggest me any solution that must include cache. Or is there any other tool similar to jmeter that could solve this issue. My goal is to take web page load time with cache for 'n' number of users.
PS : I am even interested to write any scripts in jmeter but the scripts should not overload the performance of jmeter.
Thanks in advance.
You should not be recording calls to embedded resources (images, scripts, styles, fonts, etc.) as if you record them - they will be executed sequentially while real browsers do this in parallel. So remove recorded requests for the embedded resources and "tell" JMeter to download them (and do it in parallel) using HTTP Request Defaults
You should be recording AJAX requests, however real browsers execute them in parallel while JMeter runs them sequentially. In order to make JMeter's behavior closer to real browser you need to put these AJAX calls under the Parallel Controller
You can install the Parallel Controller extension using JMeter Plugins Manager
Jmeter and caching are unrelated - everything that happens after data went over the wire is out of scope by design. You should only ever simulate requests that you expect NOT to be cached. So this is the feasible part: drop all requests that you expect the browser to cache from the Jmeter script (or move them outside the loop). On the load time of XHR: the browser will most certainly use HTTP keepAlive. Result is that all requests except the very first skip the setup and teardown phase of TCP sockets and are much faster - esp. when the request itself is small and quick. You can simulate this in JMeter also by checking the KeepAlive option AND selecting http commons as implementation. You can read up on this in the docs here: http://jmeter.apache.org/usermanual/component_reference.html#HTTP_Request
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!
I am using jMeter to load test logging in and logging out of my application. I have a CSV with 500 uname and pwords, and I have also set the active threads to 500.
Is this the correct way to stimulate a load of 500 users?
From technical perspective - yes, JMeter will pick up credentials from CSV and send them along with the request.
However if you think about what happens in reality logging in and immediately logging out doesn't seem a realistic use case for me. The whole idea of load testing a web application is simulating real users as close as possible, it includes:
Application usage scenario(s): how many users will be accessing your application at the same time and what users will be doing what things? For example given Stack OverFlow the vast majority of users are searching for answers by given criteria, some users are typing questions, some of them providing answers, and some of them are commenting. These all are different behavioral patterns which need to be accurately simulated by your load test
Each user should have a "user session" which identifies him so application would distinguish different users so make sure you have HTTP Cookie Manager in your Test Plan
Real users use real browsers which are downloading images, CSS and JavaScript files using parallel thread pool (around 5 concurrent threads) to speed up page loading process. In order to mimic this behavior you need to configure HTTP Request samplers to download embedded resources and do it in parallel. You can apply this configuration to all the HTTP Request samplers via HTTP Request Defaults.
Don't forget to add HTTP Cache Manager to mimic browser cache as real browsers normally cache embedded resources to disk and don't re-request them on subsequent calls.
So I would recommend reviewing your test scenario and/or load pattern and get familiarized with How to make JMeter behave more like a real browser article
I would like to measure loading time of a document in my testing web app. I have used JMeter for this, but I am getting different values for each run. I am measuring average time in the summary report.
I am not sure, that the value is proper or not.Is this approach is correct or Is there any plugin JMeter available?
I have used HTTP watch to get rendering time, but I can't use that tool for more than 1 user (Load Testing). I am using JMeter 2.13. Could you please help me in this?
With the help of aggregate report or csv / xml results you get required information regarding response times BUT
In Jmeter, Response time = Processing time + Latency(time taken by network while transferring data)
In Browser, Response time = Processing time + Latency + Rendering time
Hence you will found a difference between http watch response times and jmeter response times.
If you need to include rendering times also in your response times, then use tools, like loadrunner (commercial), selenium (open source) and so on. Personally in my opinion client side rendering is not a measurable value, unless all of the users accessing the application are having same configuration of hardware, software and network access. However, while JMeter test running with peak load to the system, manually browse the site using various browsers and with the help of developer tools you can find rendering times.
I am getting different values for each run - this will depends upon test data you are using, server health status, network delays and so on.
I doubt you'll be able to get 2 fully identical test run results, there always will be some form of fluctuation caused by underlying hardware and software implementations. You should be receiving similar results with some statistical noise.
If this is not the case, your JMeter test might be misconfigured. From "realness" perspective mind the following configuration:
Make sure you have Retrieve All Embedded Resources from HTML Files box checked and you Use concurrent pool. The easiest way to configure it for all the samplers is using HTTP Request Defaults
Add HTTP Cache Manager to your test plan. Previous setting "tells" JMeter to fetch embedded resources like scripts, styles, etc. from the pages. Real browsers do it as well but they do it only once, on subsequent requests these resources are being returned from browser's cache.
Add HTTP Cookie Manager to your test plan. It represents browser cookies, enables cookie-based authentication and maintains sessions.
Add HTTP Header Manager to represent browser headers like User-Agent, Content-Type, encoding, etc.
When you use a straight HTTP Protocol layer virtual user, independent of the tool (Jmeter, LoadRunner, SOASTA, Grinder, ...) then what you will be timing will be the request/response information coming from the server with very low coloration from the local processing on the client for JavaScript and the final "drawing on the screen" which is rendering.
Up until the point where the server is degraded due to number of requests or network limitations the only area where you can tune is in the page architecture, which if you are waiting to the last 100 yards before deployment to address then you are likely in trouble.
Steve Souders has written quite a bit on the subject of page architecture in his books "High Performance Websites" and related works. In short, the rule of thumb comes down to making fewer requests, smaller responses and serving the data from the closest possible location to the client. These have the effect of minimizing the most expensive finite resource to a web client, the network. For instance, a browser sprite reduces the number of calls for images, minification and compression reduce the size of the transmission and a CDN changes the number of hops to the requested item to a location closer to the end client.
In order to affect changes to page architecture you need to move upstream into your development cycle and your functional testing cycle. You will need to work with development to implement hard gates where code/pages cannot be submitted to the project without first passing performance gates related to design. Your development team and functional testing members will need to respect those gates. As to what the gates should be, I refer you back to the works of Mr Souders as a great source of data for construction of your gate rules.
This gets you to the level of "works for one: Performant for one." Then you can use that as a known good to answer the questions related to server scalability and at which point the service to the client from requests begins to degrade. If you have a CDN in your organization, be sure to take that into account in your test model, for if you do not then you will overload your server vs production.
As far as actual speeding of the "rendering" or drawing on the screen? You need to purchase a faster video card barring changes from the browser manufacturer. Speeding up JavaScript? Make sure that all of your JavaScript is as small and as lean as possible. Have your functional test team test on very dirty browsers with lots of add-ins as well as lower powered hardware for a view of maximum out of spec response. If you need a view of what your standard hardware model looks like from your clients (Browser/OS/some hardware into) then you can process the data in your HTTP request logs and specifically the user agent related to client configuration information.
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.