Re: Mutation events - slowness examples

On Wed, Jun 24, 2009 at 8:52 PM, Sean Hogan<shogun70@westnet.com.au> wrote:
> I've made a couple of tests pages for DOMAttrModified (attached).
>
> test4.html modifies (1024 times) the title on an empty div and measures
> execution time without / with DOMAttrModified listener.
>
> test5.html modifies (16 times) the title on a populated div.
> Additionally, the contents of the div are styled based on the title. eg
> div[title="After"] ul li {...}
>
> The repetition counts are chosen to get reasonable timing data.
>
> Results (approx)
> test4:
> Firefox: 25ms -> 120ms
> Opera: 35ms -> 120ms
>
> test5:
> Firefox: 43ms -> 48ms
> Opera: 50ms -> 50ms
>
> Note: Safari doesn't trigger DOMAttrModified events.
>
> Conclusion (tentative):
> The non-JS overhead of DOMAttrModified events is irrelevant to the UX, being
> well under 1ms per event.

I'm not sure I follow, 25ms -> 120ms seems quite relevant.

/ Jonas