Top JavaScript Performance Improvement Tips to Follow to Ace your Next Development
Over the past few years, JavaScript has emerged as the saving grace for next-generation Scripting developers. From servers, games, blogs, operating systems, and even robots, JavaScript is deemed as the leading scripting language. Not only that, but JavaScript is also one of GitHub’s most common languages too.
One of the most critical things when designing a website or device is performance. You can never sacrifice an application’s performance during its development time. So for developers, staying informed with the latest software practices is completely vital. It’s quite crucial to stay updated with the best performance practices.
Here, we have listed a few tips to boost the application effectively by improving the performance of JavaScript:
1. Assess local variables
JavaScript locally searches for a variable first, and then slowly extends its scope to global variables. Local variables are found on the basis of the most to the least specific scope and can be moved through different scope levels. Saving variables in a local scope enables JavaScript to have quick access to them. Keep in mind that to define the current scope yo,u need to specify the scope and also define the scope of functions by preceding each variable with ‘let’ or ‘const’. This prevents the lookup and speeds up the code as well.
2. Learn asynchronous programming
During web or mobile app development, you will require various internal calls to a number of APIs to retrieve the data. One way to solve this problem is to get different middleware per task. Since it is single-threaded, JavaScript has several synchronous components. Those components are capable of locking the entire program.
Nevertheless, the async.js function of JavaScript helps to handle asynchronous codes efficiently. This causes async code to be pushed to an event queue where it will fire after all other codes have been executed. However, even with the async feature of JavaScript, there is still a possibility to use an external library that might return to the synchronous blocking call.
3. Don’t use nested loops when not necessary
Avoiding unwanted loops like ‘for’/’while’ can keep the JavaScript in line and help in avoiding various objects from having to move through. Unnecessary loops make it difficult for users to process codes, and moreover, slow down the process.
4. Enhance cache performance
Several times, scripts are used repeatedly to access a given object. The performance can be improved immediately by storing a repeated access object inside a user-defined variable and using a variable in subsequent references to that object.
5. Build well-defined testing environments
As a developer, you need to check the applications until they go live, and testing the code requires a collection of well-defined environments. It is difficult for all versions of all JavaScript engines to do performance tests and optimization. On the other hand, if you do the research in one single environment, you can get partial results. You can go a step further and set up well-defined testing environments so that the application does not later suffer from poor results.
6. Implement Delegation for Events
With Event Delegation, managing a type of event for the entire page becomes easier using a single event handler. Because of all these event handlers, large web applications will come to a standstill without using the Event Delegation. Event Delegation advantages include:
- Less management complexity
- Fewer code-to-DOM relations
- Less memory required to process
7. Don’t use twice the same script
Duplicate scripts impact performance significantly. Duplicate scripts, particularly in the IE browser, will create unnecessary requests on HTTP Within an HTML file, using a SCRIPT tag may help prevent unintended duplication of scripts.
JavaScript has helped app development companies in providing exceptional services with its ability to churn out apps with brilliant performance.
Blog source: https://www.algoworks.com/blog/javascript-performance-improvement-tips/