On Feb 15, 2008, at 2:09 PM, Mark Baker wrote:
On 2/14/08, Kris Zyp <[EMAIL PROTECTED]> wrote:
Another functionality that I believe would be extremely valuable to
expose
for XHR would be HTTP pipelining control. Most browsers do not
provide HTTP
pipelining because of compatibility concerns and performance
implications of
improperly order requests.
I thought it was just that most proxies don't support it on the
outbound connection. And I've never seen any ordering problems from
the support, or lack thereof, of pipelining.
But I certainly agree that pipelining control would be really useful.
Last time I looked into this, there were some proxies and some origin
server configurations (in particular certain Apache modules, perhaps
now obsolete) that broke with pipelining. Since it is not possible to
find out from the server if pipelining is correctly supported, and
since it is not generally possible to tell from the response that it
has failed, enabling it by default in the browser http stack was not a
safe thing to do.
Since the breakage is caused in at least some cases by proxies, it is
not in general safe to let XHR users opt in since they may control the
origin server but generally would not control whatever proxies are
between the server and the user.
Pipelining is a great potential performance improvement and it's sad
that it can't safely be used on the public Internet right now, so I
hope we someday find a way out of the impasse.
Regards,
Maciej
