[OpenLayers-Users] Updating Data: Comet, Push, or What?

[Arnie Shore]

I'll certainly defer to others who've done measurements here, but from 
some experience with our open source computer-aided-dispatch application:

WRT " ... It seems that the "long polling" method or, worse, looped 
queries, can lead to server overload ... ."  I expect here that the 
culprit is in implementers trying to minimize latency by using an 
excessively short cycle period, which results in hammering the server.

Riding to rescue is WebSockets - http://en.wikipedia.org/wiki/WebSockets 
-  which supports server push, and for which many of us wait in eager 
anticipation.  It's a nice solution to the general problem of http in a 
real-time environment.

At this writing, the protocol spec is fairly far along but 
implementation is uneven.  I'll guess that it might be widely available 
in the latest browsers later this year.

Pending that availability, consider conventional solutions like those 
you've named, but with a reasonable cycle time.  And live with the 
latency.  (AS fast as these boats are, they remain sailboats!)

AS


On 5/20/2011 10:14 AM, Michael wrote:
 > Greetings Mappers!
 >
 > I've built a trans-pacific charting application intended to be used for
 > near real-time sailboat tracking.