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In the case of websites, the term Performance or performance, refers to the load speed or computing power of a server, that is, the speed at which data is transmitted from the server to the client.

Reasons for good performance

A website that loads slowly can encourage potential customers to leave the page. To ensure smooth interaction, something has to be done proactively to achieve good performance. Fundamentally with the increasing use of mobile devices, a positive impression through discreet and fast loading is essential to convert visitors into customers. When a page loads slowly, the visitor may bounce and then click on a competitor's search result. The performance of a website has gained in importance because websites are getting bigger and networks are getting slower due to higher loads.

Advantages of good performance

Smooth interaction with a web portal keeps visitors there and builds trust. At the same time, operating costs can be reduced. Better performance also means decreased site speed, which can have a positive effect on search engine rankings.

Optimization options

There are many ways to improve web performance. Only a few can be cleared in a few seconds. Not all methods are advisable for all websites, so you should always check before the execution if the effort will pay off or not.

Using the browser cache

It is workable to cache the files, that is, to buffer them on the client side. For example, if an image is cached on the first visit to that page, it can be loaded from there for the second visit. The page will load faster because the image does not have to be transferred. Caching is only useful for files that don't change often. A respective entry must be made in the .htaccess file for this to run.

Precompression with gzip

Another way to reduce loading time is compress the data before it is sent by the server. This is done using gzip in the .htaccess file. HTML, CSS, JavaScript and other types of files can be compressed. At the same time, blanks and comments can be erased earlier. The reception of this compressed page is compatible with current modern browsers. It is feasible to cut the loading time in half with gzip.

Decrease in HTTP requests

Each element of the page is an HTTP request. A browser can load between two and eight of these items at a time, all the others enter a kind of queue. This takes longer to load a page completely, regardless of the available bandwidth.

  • The number of HTTP requests can be reduced combining certain items on the page. The most used graphics can be combined into a single unit, which would be recommended for navigation items. This principle is called CSS sprites because CSS is used to describe when and what items are visible. Another viable alternative is JavaScript.
  • Multiple CSS files or JavaScript libraries can be combined into one.
  • At the same time, old and unnecessary files can be deleted to further reduce HTTP requests. Items without function are unnecessary and they only generate unnecessary requests.

Another advantage of having fewer requests is that each file has its own header. It has to be sent with every request and thus grouping graphics or CSS files makes sense.

Keep file sizes small

To reduce the total amount of data to be transmitted, files they must be small. The increase in bandwidth is not an argument, because currently there are to pay attention visits with mobile devices.

  • One way to reduce file sizes is to avoid duplication. Both CSS code and JavaScript code often contain paragraphs that are repeated elsewhere. If these are cleverly placed in external files, repetitions and thus the file size can be reduced.
  • Control characters present another way to reduce file size. A programmer ideally respects the readability of code, thus including tabs, blank lines, and line breaks. It consists of characters that are transferred unnecessarily. Special tools allow you to automatically remove superfluous characters from CSS, JavaScript or HTML files. The resulting version is hardly usable, but it is smaller than the textured version and thus more suitable for shipping.
  • Graphics offer great space saving potential. File size can be greatly influenced by intentional downgrading of quality. The format can be chosen when saving, the size must be precisely the same as the graphic is displayed, and during compression the parameters that impact the file size can be changed (JPEG 85% produces a smaller file than JPEG 100%) .

Check cookies

Cookies also impact performance. Any cookie and any information in a cookie should only exist if it is useful. For example, the collection and transmission of data that simply will not be used can be dispensed with.

CSS selectors

In addition, small improvements can be made in the CSS style sheets. The reason is that CSS selectors have different processing times. The most suitable are ID (#) and class (.). Regardless, the wildcard selector (*) and descendant selector (>) are slower. Another small factor is the @import command, which can block loading in some browsers until the imported file itself loads.

Relevance for SEO

Site speed is a confirmed ranking factor and thus performance is important from an SEO perspective. At the same time, visitors quickly leave pages that load slowly. It can be reduced to milliseconds. Large websites have frequently tested the impact of performance on customer behavior. Amazon, for example, intentionally delayed the loading time of product pages by 100ms. As a result, sales decreased by one percent.

In a Yahoo study, the loading of the home page was delayed by up to 400ms, with the result that nine percent of visitors closed the page before the loading was complete. The shopping search engine Shopzilla reduced its loading time by 3.5 seconds thanks to performance optimization. Revenues then increased by twelve percent. Performance optimization thus occurs as part of search engine optimization. For comparison, it would be advisable to also examine the websites of competitors with the appropriate tools. Google Insights is a tool that can be used for this. You can specify a URL that is being tested for site speed. The tool will generate proposals to boost the loading speed.