Thanks for your informative reply.
In my case I think I should have only at most two concurrent request
at any time. But what I really need is to be able to abort a pending
notify request. If I can, then I will have at mot one request at a
Basically I will have a pending notify request until the server
replies to it. But if I need to change a state from the client, I need
to abort the notify request, change the state and then send a new
notify request.
Is it possible to abort a pending request from thr prototype
framework ?

How do ajax application manage to get informed of server side events ?
Do they all rely on polling method ?


On Jan 16, 7:01 pm, "T.J. Crowder" <> wrote:
> Hi Christophe,
> > Is there a limitation with prototype with request like notify ?
> Not in _Prototype_.  But there are lots of limitations around
> concurrent requests imposed by various browser and server
> implementations.  Most browsers will only ever process two concurrent
> requests to the same server, queuing the others.  I don't know that
> anyone (IE, Firefox, etc.) _documents_ that they will guarantee to
> process the queued requests in the order that you initiated them (and
> you certainly can't count on them _completing_ in order).  Separately,
> some servers implement a similar limitation on concurrent requests
> from the same client, and again, I'd be surprised (especially once you
> get into a scaling situation with a server farm) if you could rely on
> concurrent requests being processed strictly in order of initiation.
> In situations where you need the requests processed in a strict order,
> you'll need to implement a queue in your client-side code and wait for
> the result of one request before initiating the next.  And you'll
> probably need to only rely on having one request satisfied at a time,
> although in most cases you could have two.
> Note that all this is not just "Ajax" requests.  This applies to page
> loads involving lots of images, style sheets, script files, etc.
> HTH,
> --
> T.J. Crowder
> tj / crowder software / com
> Independent Software Engineer, consulting services available
> On Jan 16, 12:26 pm, cb <> wrote:
> > Dear All,
> > I am trying to implement a web UI for a web service that provides
> > XML requests to get synchronously some state values
> >   for example, /state1/get
> > XML request to change some state values
> >   for example /state1/up
> > and a NOTIFY request for which it will only answer when the state
> > change
> >   for example /state1/notify
> > My understanding is that prototype can handle multiple requests.
> > The problem I am facing is that some requests seem to be stuck while a
> > notify request is pending. Moreover when I get an answer for a pending
> > notify, it looks like all requests that were stucked, are sent but in
> > a out of order.
> > Is there a limitation with prototype with request like notify ?
> > Is there a way to cancel/abort a pending request ?
> > Thanks,
> > Christophe
You received this message because you are subscribed to the Google Groups 
"Prototype &" group.
To post to this group, send email to
To unsubscribe from this group, send email to
For more options, visit this group at

Reply via email to