animated gifs - impact on httpd access.log -Reply

[Albert Kemp Jr.]

In addition to Frank's comments, the "server push" method is far more
intensive on both cpu resources and bandwidth, because each frame of the 
animation is "pushed" to the client according to server load.  As the
animation plays, the connection to the server must remain open, as the
CGI pushes the next frame thru.  This method would obviously fill the
access log of any Web server, especially if the web page was a popular
one.  IMHO, the only advantage to using this method is that you can
"push" either .JPG or .GIF files.  Although, transparency is lost on 
the JPG format.  Thus, the advantages of multi-image "GIF animation" 
become more apparent.

However, it should also be said that nobody appreciates the gross misuse 
and poor implementation of animation, whether it be server or GIF driven.
As has already been mentioned on this list and others, such pages are
difficult to load and therefore frustrating to navigate, as animation
can interfere with hyperlinks and other interactive features of a web
page.

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Albert Kemp Jr.           [[][][]]   Net: akemp at library.uwaterloo.ca
Library Asst., Systems    [[][][]]   Web: http://www.lib.uwaterloo.ca/~akemp
University of Waterloo    [[][][]]   Fax: (519) 746-1758
Ontario, Canada  N2L3G1    ######
(519) 888-4567, x5377    [[](||)[]]
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On Wed, 13 Nov 1996, Frank Cervone wrote:

> Both methods (push-pull and animated gifs) give you the appearance of
> animation. An animated gif places the burden of displaying the animation
> on the client's browser.  All of the images are downloaded once as part
> of a single file and the browser cycles through the images in the file
> without any further interaction with the server.  Push-pull on the other
> hand retrieves each animation image from a seperate file on the server.
> For each animation image, the browser has to request the next file from
> the server.  Push-pull was an early, primative attempt to implement
> animation, but it still has some limited use. An example would be moving
> from one page to another after a certain amount of time has elapsed.  It is
> not appropriate, however, for fast moving, multiple image animation. The
> animated gif format was developed partially as a reaction to the
> incredibly negative impact fast-moving, multiple image push-pull animation
> has on a server.
> 
> Frank Cervone
> Assistant Director for Systems
> DePaul University Libraries
> 2350 North Kenmore Avenue
> Chicago, IL  60614
> 773.325.7000 ext 1114 
> 773.325.7869 (fax)
> 
> >>> Walter W. Giesbrecht <walterg at YorkU.CA> 11/12/96 07:56pm >>>
> I thought animated .GIFs were simply a series of images stored in the 
> same file. The file would only be served up once, but would continue  to
> be animate _ad nauseum_ once it reached the requesting client.  Unless
> push-pull animations are different, of course ...
> 
> ------------------------------------------------------------
> Walter W. Giesbrecht                        walterg at yorku.ca     York
> University Libraries          (416) 736-5639 ext. 77551
> North York, Ontario, Canada
> 
> 
>