Investigating the Evolvability of Web Page Load Time

TL;DR

This paper explores a mutate-and-test approach to optimize web page load time by making code changes in Javascript, achieving significant performance improvements in a benchmark scenario.

Contribution

It introduces a method using code deletion operators and explores code mutation to improve web page load performance, demonstrating a 41% load time reduction.

Findings

Optimized load time by 41% in benchmark web page.

Code deletion operators can effectively improve performance.

Mutate-and-test approach is viable for web performance optimization.

Abstract

Client-side Javascript execution environments (browsers) allow anonymous functions and event-based programming concepts such as callbacks. We investigate whether a mutate-and-test approach can be used to optimise web page load time in these environments. First, we characterise a web page load issue in a benchmark web page and derive performance metrics from page load event traces. We parse Javascript source code to an AST and make changes to method calls which appear in a web page load event trace. We present an operator based solely on code deletion and evaluate an existing "community-contributed" performance optimising code transform. By exploring Javascript code changes and exploiting combinations of non-destructive changes, we can optimise page load time by 41% in our benchmark web page.