Various Notes

First, I’m gonna be at OSCON the same week that TAE is going down. If you were counting on me buying you beer while in SF, you’ll have to collect from Dylan (he’s good for it) or one of the other Dojo’s.

Next, can y’all please stop conflating Comet with a particular HTTP-level mechanism for achieving the stated user interaction goal? It’s getting quite tiresome to hear folks say things like “long polling or Comet” as though they’re different. The XMPP HTTP binding guys even go to great lengths to explain how their Comet technique (BOSH, aka: “long-polling”) isn’t Comet. Almost as entertaining as it is wrong. Long polling along with other techniques are ways of implementing the basic Comet pattern. The general description of the pattern contains no preference for one or the other. It only requires that you not naively poll N seconds.

Lastly, I’d like to express my disappointment that Jack didn’t include Dean‘s excellent Base2 in his latest round of benchmarks. It’s doing us all a disservice that he’s not including the fastest engine around in his benchmarks.


  1. Posted July 12, 2007 at 11:12 pm | Permalink

    “It’s doing us all a disservice that he’s not including the fastest engine around in his benchmarks.”

    I have a lot of respect for Dean Edwards work so I tested base2 in the slickspeed environment on my local machine. It was not the fastest – generally was in 4th behind Ext, jQuery and dojo.query except in FF where it was last. It also had quite a few errors in IE7, as none of the attribute selectors worked.


  2. Posted July 13, 2007 at 7:04 am | Permalink

    Thanks for mentioning base2 Alex. I think it is probably the fastest engine overall (although Jack’s is pretty formidable). It is also very accurate across all browsers as it has had years of testing in the form of cssQuery. I uploaded the slickspeed test suite so you can try it yourself:

  3. Posted July 13, 2007 at 11:32 am | Permalink

    wild …I didn’t even know about Base2 (this is why I have your blog on my front page RSS radar.  keep the great info coming).  Also refreshing to see that you want to see the benchmarks to help drive faster speeds for all libs as a whole, not just Dojo. 

  4. Posted July 13, 2007 at 4:56 pm | Permalink

    Dean, where is that version of base2? That is definitely a different version than the one I downloaded from your site.

    When I run the tests on your new version, base2 is fastest in FF and Ext is faster in every other browser. Do you see different results?


  5. Posted July 14, 2007 at 1:24 am | Permalink

    @Jack – the latest (dev) version of base2 is here:

    I recently updated base2 after adding back the XPathParser (that’s why it is so fast on Firefox). base2 is still in development and is not “officially” released. I’m constantly updating the code before a full release.

    I just run on Win32 and base2 was fastest for IE7, Opera 9, and Firefox 2. Ext was fastest for Safari 3. But I find that times can vary quite a lot TBH.

    Your nth-child query still kicks my butt on IE7. I want to know your secret. :-)

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  1. […] Various Notes Dojo’s Alex Russell wishes that Jack Slocum’s analysis of CSS selector performance had included Dean Edwards’s Base2 library, claiming it’s the fastest implementation around. This point is debated in the ensuing comments. (tags: javascript ) […]