YDN Theater — Julien Lecomte: “High Performance Ajax Applications”

By YUI TeamDecember 20th, 2007

Julien Lecomte of Yahoo delivers a tech talk on high-performance Ajax web-development.

Julien Lecomte, author of the YUI Compressor and the YUI Browser History Manager, recently gave a talk at Yahoo on the creation of high-performance DHTML applications.

In this talk, Julien covers several major performance topics:

  • Developing for high performance
  • High performance page load
  • High performance JavaScript
  • High performance DHTML
  • High performance layout and CSS
  • High performance Ajax
  • Performance measurement tools

Julien was kind enough to let us shoot video, and Ricky Montalvo from the Yahoo! Developer Network did the editing. I know Julien would love to hear your questions and feedback in the comments section.

src="http://cosmos.bcst.yahoo.com/up/ypp/default/player.swf" type="application/x-shockwave-flash"

In Case You Missed…

Some other recent videos from the YUI Theater series:

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  1. [...] High Performance AJAX Applciations – A Yahoo talk about this issue, it starts out slow but there are some really good tips given. [...]

  2. [...] YDN Theater — Julien Lecomte: “High Performance Ajax Applications” » Yahoo! User Interface Bl… # Developing for high performance (tags: yuiblog.com 2007 mes11 dia21 at_tecp javascript ajax Yahoo! blog_post performance apresentação *****) [...]

  3. [...] from the Yahoo! Developer Network, were kind enough to shoot the video, edit it, and put it on the YUI Blog. In this talk, I cover the following [...]

  4. [...] Yahoo como criar aplicações Ajax com alto desempenho, 2007-12-22: Slides (Flash, em SlideShare), Vídeo e PPT (em YUI Blog) da apresentação “High Performance Ajax Applications”, por Julien [...]

  5. Your presentation is great! Very helpfull. Thank you.

  6. [...] Lecomte: "High Performance Ajax Applications" (YUIBlog | .m4v [...]

  7. Hi

    I was surfing and found this article.
    I,m from Poland. It’s realley very interesting presentatiom.

  8. [...] Anyway, to skip to the present, starting work on the RSF/Fluid client-side renderer, I felt similarly at sea on how to plan for a design that runs efficiently. Javascript is starting to emerge from its “ghetto folkloric” period and to become the target of determined engineering efforts, and there are a number of resources round the web focused on Javascript performance issues, such as John Resig’s excellent blog entry collection http://ejohn.org/blog/tags/performance/, and a splendid presentation by Julien Lecomte of YUI http://yuiblog.com/blog/2007/12/20/video-lecomte/. [...]

  9. [...] more information check the YUI theatre’s “High Performance Ajax Applications” by Julien [...]

  10. [...] Lecomte: "High Performance Ajax Applications" (YUIBlog | .m4v [...]

  11. [...] JavaScript code as he has authored the YUI Compressor as well as the YUI History Manager. In a talk given by Julien, he gives some excellent advice on JavaScript optimization. During the presentation [...]

  12. Maybe it has been too long from the talk date but all the links are broken – no download and no embed is working.

  13. @Joe — You’re right, the video is no longer available for download. I’ve updated the post. The embed still works for me, though; you should be able to watch that on a Flash-enabled browser. -Eric

  14. can’t see in embedded form, and no download.
    Seemingly useful and interesting video, but can’t really watch it…

  15. @vadrer – Thanks for letting me know — this should be fixed now. -Eric

  16. thank you, Eric, the video is now available, indeed.
    very useful :)

  17. I’m trying to watch this video probably over a bit slower network connection and am having a bad time. The video keeps breaking frequently for buffering and doesn’t buffer even 20 secs of continuous video at a shot. It’s impossible to watch the video with so many breaks. So, I left the video paused in the hope that it will buffer a bigger chunk that I can then watch comfortably, and it worked a couple of times but the video restarted during my third attempt to do the same. And guess what? On restart, it’s back to the buffering mode right from the start (nothing seem to have got cached on my machine) and my bad experience continues. The same happens when I rewind a bit in the hope to get a continuous feed. Is it possible to make this video available for download? Or at least host it on youtube so that people with slower connections can watch it better (youtube player does a good job caching the video locally – at least when I rewind, I get a continuous video of the overall buffered chunk)?

  18. Amit — I’m sorry for the bad experience you’re having. Unfortunately, this is one of the very few YUI Theater videos that I didn’t shoot and edit myself. The team that shot the video subsequently removed the downloadable version, and I don’t have a copy of it. My apologies. -Eric

  19. thanks for your reply, Eric. Ok, can you think of anything that might help me… maybe some software you know abt that can rip off this video? …or probably, any way to contact someone from the shooting team; they just might have a copy to lend me :) …or, anything else.. the video seems to be quite popular and I don’t want to miss it… thanks for your help

  20. Amit — No, I don’t know of any good solution for you other than to play the video from a different (higher-speed) connection at the next opportunity. Sorry about that. All of the recent work on YUI Theater has download options, and the most recent stuff I’m posting in HD…but the source file for this one is no longer available. -Eric

  21. Never mind, Eric. Thanks for letting me know.

  22. [...] For more information check the YUI theatre’s “High Performance Ajax Applications” [...]

  23. [...] engineer and the author of YUI Compressor and YUI Browser History Manager. Julien writes and speaks about issues of web application [...]

  24. [...] more information check the YUI theatre's “High Performance Ajax Applications” by Julien [...]