W3C home > Mailing lists > Public > ietf-http-wg-old@w3.org > September to December 2000

RE: Http overhead

From: Joris Dobbelsteen <joris.dobbelsteen@mail.com>
Date: Fri, 1 Dec 2000 22:24:25 +0100
To: "WWW WG (E-mail)" <http-wg@cuckoo.hpl.hp.com>
Message-ID: <000001c05bdd$15062c40$01ff1fac@Thuis.local>
You are right, I did know this.

Indeed that's why I favor chunked encoding for dynamic resources. MSN's
(search) server (MS-IIS) transfers the data by just closing the
connection at the end (not sending any indication about the size of the
document) what also decreases the transfer 'reliability' - or better,
you don't know wether you have all or not... HTML or JPEG/GIF you can
guess it, but with many other sources you don't (like TXT)....

Also MSN's server has thus more overhead for the server and waisted time
between the requests for the client...

- Joris

> -----Original Message-----
> From: francis@localhost.localdomain
> [mailto:francis@localhost.localdomain]On Behalf Of John Stracke
> Sent: Friday 01 December, 2000 16:04
> To: WWW WG (E-mail)
> Subject: Re: Http overhead
> 
> 
> Joris Dobbelsteen wrote:
> 
> > Many apache servers send data chunked. Takes a couple bytes 
> (average of
> > 4) for every block transfered. Maybe a total overhead of an 
> additional
> > 20-40 bytes per transfer (maybe less). This is just a guess...
> 
> Yes, but it's actually better than that: AFAIK, Apache uses chunked
> transfer-encoding only for dynamic resources, where it can't 
> predict the
> content-length.  The alternative would be (a) buffer the output before
> sending it down, or (b) defeat persistent connections.  
> Either (a) or (b)
> would increase; (b) would actually cost extra bandwidth, and (a) would
> cause bandwidth consumption to come in spikes.  So, most 
> likely, the cost
> of chunking is lower than the cost of not chunking; it's 
> certainly lower
> than the nominal overhead of the encoding.
> 
> (Sorry to those to whom this is obvious--probably including 
> Joris--but I
> didn't want to leave anybody thinking they could save 
> bandwidth by turning
> off chunking.  :-)
> 
> --
> /=================================================================\
> |John Stracke    | http://www.ecal.com |My opinions are my own.   |
> |Chief Scientist |================================================|
> |eCal Corp.      |In the country of the blind, the one-eyed man is|
> |francis@ecal.com|in therapy.                                     |
> \=================================================================/
> 
> 
> 
> 


Received on Friday, 1 December 2000 21:26:15 EST

This archive was generated by hypermail pre-2.1.9 : Wednesday, 24 September 2003 06:33:40 EDT