Intriguing stuff! I found this generic-ish article about perl: http://www.perlmonks.org/?node_id=83791
The implication is that unless/until Mapserver starts sending Content-Length along with returned images, browsers won't do keep-alive for us. More performance! P. On Wed, Sep 17, 2008 at 10:26 AM, Jim Klassen <[EMAIL PROTECTED]> wrote: > I have found there is a fairly large overhead inherent in the HTTP request > (per tile) especially if the network round trip times are an issue. Using > HTTP keep-alive helped a lot with this. > > Awhile ago we did some tests at the city when we were looking to go to a > tiled interface. What we found was along the lines of a 100x100px tile > request takes much more than 1/4 of the time of a 200x200px request so the > overall map load time was slowed by using more tiles when getting the tiles > from mapserver. This would probably be different if we had used a tilecache. > In the end we found not tiling (a.k.a. 1 tile per map) worked best for us > from a speed/flexibility focus. > > JimK > >>>> "Paul Ramsey" <[EMAIL PROTECTED]> 09/17/08 11:14 AM >>> > John, > > The idea that CGI is naturally a much slower situation than a > long-running process is a bit of a red herring in the case of > Mapserver, and I say that as someone who is anal retentive about these > things. Unless your Mapserver installation has some naturally latent > components (database connections, primarily) you'll find that moving > from CGI to FastCGI is worth about 15ms per request. > > On Wed, Sep 17, 2008 at 8:40 AM, John Westwood <[EMAIL PROTECTED]> wrote: > >> The reason I am trying to get MapServer to work with fast_cgi is because I >> am experiencing poor performance with OpenLayers. I believe that OpenLayers >> starts a new MapServer instance for each tile request, thus causing an >> unnecessary overhead. Am I correct? > > Yes and no. If you are experiencing noticeably poor performance (you > can actually *see* it being slow) the only place that the CGI overhead > could be the cause is if you're connecting to Oracle or SDE for some > of your layers. If that's not the case, look elsewhere first, the very > small gains you will receive from moving to FastCGI will not change > your underlying problem. > > Paul > _______________________________________________ > mapserver-users mailing list > [email protected] > http://lists.osgeo.org/mailman/listinfo/mapserver-users > > _______________________________________________ mapserver-users mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/mapserver-users
