Performance Testing is a type of testing to ensure software applications will perform well under their expected workload. Performance testing is the type of Non-Functional Testing. There are different tools to measure the performance of the website. We are going to explore Webpage test performance testing tool, explained as below :
WebPagetest is used for measuring and analyzing the performance of web pages. Webpagetest enables you to run web performance tests on your site from a number of different locations across the world in a number of different browsers.
- Visit - https://www.webpagetest.org/
- Select Simple Testing to perform simple tests
- Enter URL that needs to be tested.
- Select the Test Configurations (Either Desktop, Mobile testing)
- Include Repeat View (Only if required)
- After everything is configured click on Start Test button. The request will be sent to the selected location for testing.
Note:The test may take time depending on how many tests are ahead of yours.
Lets us understand the terminologies used in the Webpage test tool.
Following are some of the optimization grades shown after the test is completed.
- Keep-alive Enabled
- Compress Text
- Compress Images
- The image compression check just looks at photo images (JPEG files) and makes sure the quality isn’t set too high. JPEG images can usually be compressed pretty substantially without any noticeable reduction in visual quality.
- Cache Static Content
- Combine JS/CSS Files
- Use of CDN
- Each request for a piece of content to the web server has to travel from the user’s browser all the way to the server and back. As you get further and further from the server this can become a significant amount of time (which adds up quickly as there are more requests on the page). Ultimately the time it takes is limited by the speed of light so there’s not much you can do except to move your server closer to the users.
Following are some of the page level metrics captured and displayed for the overall page.
- Load Time
- The Load Time is measured as the time from the start of the initial navigation until the beginning of the window load event (onload).
- Fully Loaded
- First Byte
- The First Byte time (often abbreviated as TTFB) is measured as the time from the start of the initial navigation until the first byte of the base page is received by the browser (after following redirects).
- First View
- The First View row is a test that was done with a browser that had its cache and cookies cleared out and represents what a first-time visitor to the page will experience.
- Repeat View
- The Repeat View row is a test that was done immediately after the First View test without clearing out anything. The browser window is closed after the First View test and then a new browser is launched to do the Repeat View test.
- Start Render
- The Start Render time is measured as the time from the start of the initial navigation until the first non-white content is painted to the browser display.
- Speed Index
- The Speed Index is a calculated metric that represents how quickly the page rendered the user-visible content (lower is better).
- DOM Elements
- The DOM Elements metric is the count of the DOM elements on the tested page as measured at the end of the test.