Re: [NavigationTiming] incorrect description for requestStart

    Thanks, Chris and Jason. Some good questions you have brought up.

On Thu, May 19, 2011 at 5:33 PM, Christian Biesinger
<cbiesinger@gmail.com>wrote:

> Hi,
>
> I just noticed a bug in the description for requestStart (Thanks jduell):
> > This attribute must return the time immediately before the user agent
> starts requesting the current document. It is set prior to checking HTTP
> cache.
>
> >From what I remember from the discussions and from the timeline below,
> the "HTTP cache" sentence should be removed here, because this
> attribute refers to the time immediately before the UA starts
> write()ing to the socket. Otherwise, this would be identical to
> fetchStart (which does have similar cache wording).
>

   "requesting the current document" can be to the network or the cache. In
case it's done through
the HTTP cache, domainLookupStart/End and
connectionStart/End/(secureConnectionStart if
available) should all be equal to fetchStart because they are non-existing,
and requestStart is
the beginning of the process to fetch resource from the cache.
   This is captured by our discussion here:
   http://lists.w3.org/Archives/Public/public-web-perf/2010Sep/0036.html

   fetchStart starts before checking of the app cache, which is different
from http cache here.

cheers,
Zhiheng



>
> -christian
>
>