Re: nsGenericElement::InsertBefore performance

Simon Paquet wrote:
> On 12 Mrz., 17:39, Boris Zbarsky <[email protected]> wrote:
>   
>>> Do you have any *high-level* suggestions on how to make our CSS rules
>>> faster?
>>>       
>> http://developer.mozilla.org/en/docs/Writing_Efficient_CSSseems to cover it.
>> The one thing that jumped out at me was the use of the ' ' combinator.  That's
>> usually a bad idea performance-wise.
>>     
>
> Thanks Boris.
>
> I posted a summary of your findings to mozilla.dev.apps.calendar. See
> the post with the Message-ID <[email protected]>. We
> would be happy for any further suggestions that you might have.

I'm glad my little investigation triggered a profound look upon this 
issue, resulting in some hints how to improve the current performance.

Still, playing devil's advocate, I'm wondering if optimizing CSS rules 
will be enough to yield the necessary speed up of at least 1000 %, which 
would still be dead slow on Boris' test machine. To me, the problem 
seems fundamental, in the sense that typical application programming 
technique (adding an item to a listbox is a microsecond action) is 
applied to XUL-programming, resulting in deep CSS interpretation again 
and again. That's why I've been suggesting caching techniques beyond XBL 
caching. All calendar-month-day-box-item have limited individual 
property variations, and could reuse the same set of "compiled" 
definitions (which might be not all that easy...).

Regards,
Andreas