Re: [XHR2] ArrayBuffer integration

On Tue, Sep 28, 2010 at 9:39 AM, Boris Zbarsky <bzbarsky@mit.edu> wrote:

> On 9/28/10 10:32 AM, Chris Marrin wrote:
>
>> I'd hate the idea of another flag in XHR. Why not just keep the raw bits
>> and then convert when responseText is called? The only disadvantage of this
>> is when the author makes multiple calls to responseText and I would not
>> think that is a very common use case.
>>
>
> It's actually reasonably common; Gecko had some performance bugs filed on
> us until we started caching the responseText (before that we did exactly
> what you just suggested).
>
> Oh, and some sites poll responseText from progress events for reasons I
> can't fathom.
>

A number of sites check .responseText.length on every progress event in
order to monitor how much data has been received.  This came up as a
performance hotspot when I was profiling WebKit's XHR implementation as
well.

- James



>
> -Boris
>
>

Received on Tuesday, 28 September 2010 19:06:08 UTC