[OpenLayers-Users] Performance Issue with multiple layers

[Gregor Mosheh]

Marc Desharnais wrote:
> I'm using the library from the openlayers website.
> http://www.openlayers.org/api/OpenLayers.js
> I guess it precompiled.
> In fact I don't link the website, I have downloaded the openlayers.js 
> and the server and load it in LAN.

Ah, okay. Then it's already compressed. Just checking, as that affects 
the load time significantly!


> But regarding the cpu consumption, is it normal that openlayers responds 
> better on a faster machine on the client side?

Somewhat. On older machines (1 GHz P-III with no video card worth 
mentioning) I find that the maps are jumpy. That goes for Google as well 
if I do a lot of overlays on it.

I was originally going to suggest the scientific method: Trim the map 
down to 1 layer, see whether it's slow, optimize it. Repeat. Perhaps 
your WMS/WFS server isn't doing the best job it can due to how the data 
is organized. Perhaps 7 layers is a bit much.

Then again, there's everyone's favorite solution to slowness: TileCache. :)


-- 
Gregor Mosheh / Greg Allensworth
System Administrator, HostGIS cartographic development & hosting services
http://www.HostGIS.com/

"Remember that no one cares if you can back up,
  only if you can restore." - AMANDA