Re: pipelining vs. deferred content
Jeff de la Beaujardiere (delabeau@iniki.gsfc.nasa.gov)
Thu, 27 Mar 1997 10:02:11 -0500
Jeffrey Mogul writes:
> Actually, this doesn't entirely solve the problem. If you have an HTML
> file with, say, 41 embedded images, and image #3 will take 10 seconds to
> precompute at the server, you would really like to be able to use the
> network to load images #4 - #41 while that is happening. The IMG tag
> allows the browser to render the bounding box, but it doesn't solve the
> retrieval serialization.
Thank you for restating what I had not stated clearly enough. I am indeed
referring to a situation wherein the image will not yet exist if the client
requests it immediately upon parsing the HTML.
> Another approach that would probably work with HTTP/1.1, but would not be
> compatible with HTTP/1.0 clients, would be for the server to respond to
> the initial request for the "slow" image by sending
> HTTP/1.1 503 Service Unavailable
> Retry-after: 10
Interesting idea which should help with pipelined requests. It does,
however, require invoking a second script on the server. I want a single
response to send HTML, pause while the image is generated, and then send the
image.
> I think this is a problem worthy of some more thought, but I doubt we'll
> solve it before we need to progress HTTP/1.1 to Draft Standard.
I would not dream of suggesting that this idea be included in 1.1.
--Jeff dLB
= J-F Pitot de La Beaujardiere
= delabeau@iniki.gsfc.nasa.gov
= http://globe2.gsfc.nasa.gov/