- From: Kang-Hao (Kenny) Lu <kanghaol@oupeng.com>
- Date: Mon, 14 Oct 2013 04:41:57 +0800
- To: HTML5 Performance Task Force <public-html5-performance@w3.org>
With my experience with HTML5 games, I have the feeling that JavaScript
performance is too overlooked and it's worth mentioning it in the wiki
page. Some of the HTML5 games we encounter are slow becasue
* Huge prototype tree makes inline cache too big to the point that
inline cache matching becomes the bottleneck.
* JS objects fall into dictionary mode when they shouldn't.
I think Web apps that are not games might share these problems, but I
don't have too much expereience so I can't be certain. It's possbile
that ES6's Map and the new class syntax alleviates problems like this,
but I am not too enthusastic, given that ES6 has a bunch of syntax suger
that needs to be standardized.
I am not going to propose crazy and highly anti-competitive solutions
such as standardizing the "dictionary mode vs. fast mode" heuristics,
but I do hope that SpiderMonkey and JavaScriptCore have that documented
somewhere (I already go through Carakan and V8 and I don't have the
passion to do two more JS engines). So yes, I think having good
documentation of all the JS engines is a good solution.
Cheers,
Kenny
--
Web Specialist, Opera Sphinx Team, Oupeng Browser, Beijing
Try Oupeng: http://www.oupeng.com/
Received on Sunday, 13 October 2013 20:43:31 UTC