Thursday, June 7th, 2007
JsLex: Profile your Ajax applications
Category: JavaScript
, Utility
JsLex is a tool to profile your Ajax applications:
Working on the Apache XAP project and Nexaweb's Universal Client Framwework, which has a large code base it became apparent that hand injection of profiling code only worked so well. A new technique was needed to make it possible to capture a complete view of the performance of an Ajax application in a similar way to using jProfile for Java code.
You install the JsLex application and then add in the JavaScript library:
JAVASCRIPT:
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<script type="text/javascript" src="http://localhost/jsLex/javascript/jsLex.js"></script>
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At this point you can hit the JsLex app, and you get all kinds of metrics:
4.6 rating from 17 votes
this is very cool.
How does this differ from the profiler in Firebug?
This profiler works both in firefox, mozilla, IE, safari, …
Many of the performance issues that people run into aren’t on firefox. The ability to use it on any browser allows users to touble shoot problems where they happen.
so it will work under IE6/IE7?
It’s too much of a hassle for me to install, and Firebug’s profiler is “good enough” for me. That “Call Graph” button in the screenshot makes me curious though. I’ve been thinking for a while of whipping up some quick and dirty call graph generator (combining Firebug and Graphviz) myself.
Is there a user forum somewhere for jsLex?
What would make this absolute gold is code coverage. Tie this in with a testing suite and let me see how much of my code is actually getting profiled, down to single lines.
Is there a possibility to compare my website with other websites?