[OpenLayers-Users] WFS Layers blocks excution?

[Christopher Schmidt]

On Wed, Jun 06, 2007 at 09:13:49AM +0800, Jackey Cheung wrote:
> I've updated to 2.4, it do improve quite a lot, but I'm still suffering 
> noticeable (little, but still noticeable) lag while panning, and it takes 
> around 1 second to load the layer when refresh. Is this normal?

I would say you're probably dealing with pretty standard behavior at
this point, yes.  If you get Firebug (debugging extension for Firefox)
you can watch the time that requesting data from the server actually
takes: this may help you determine whether your 1 second refresh time is
server or clientside.

> You've mentioned about pathological dataset. I'm using MapServer as the WFS 
> server, returns 3 data fields (ID, Name, coord) in GML. Isn't it general? 
> If you were referring to the server side process, I just wondering, does 
> server side process affect the execution flow of the client side?

The server side execution doesn't affect the client.

> What should I focus on to tune this WFS thing in OpenLayers?

First, get firebug and time the requests.
Second, turn on profiling and check out the time to do things in
Firefox. (You can't do this in IE, but the performance is going to be
mostly the same -- issues generally show up in both.) If you're seeing
major differences between IE and Firefox, my best advice is basically
"Good luck". I don't have any experience or advice in debuggin speed
issues in IE.  

Regards,
-- 
Christopher Schmidt
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