RE: javascript trick redux

"Adam Rifkin" <[email protected]> Sat, 10 May 2003 17:17:17 -0700
Newsgroups gmane.comp.web.mod-pubsub.general,gmane.comp.web.mod-pubsub.devel
Message-ID <[email protected]> 
Hi Dave,

I will let Lucas answer as to whether he cares to share his .NET server.

The problem with .NET/IIS closing connections is similar to the problem =
Java application servers cause, too, in the name of scalability.  =
They're built to close connections as quickly as they can so they can =
vend new incoming requests with greater quality of service.

What you're doing at http://www.bangeye.com/pubsub/ is certainly similar =
to what we're doing.  Nicely done!

Ka-Ping Yee demonstrated this technique using animated gifs almost four =
years ago:

   http://zesty.ca/chat.html

but when I go to that site today, it doesn't quite work.

Other similar projects are:

   Pushlets - http://sourceforge.net/projects/pushlets/
       http://www.pushlets.com/

   OpenThought - http://sourceforge.net/projects/openthought/
       http://www.openthought.net/

I'm Cc'ing Just and Eric on this note just to give them a heads-up and =
thank them for teaching the world about HTTP streaming techniques.

   Adam



-----Original Message-----
From:	[email protected] [mailto:[email protected]]
Sent:	Sat 5/10/2003 1:04 AM
To:	[email protected]
Cc:=09
Subject:	[Mod-pubsub-developer] RE: [Mod-pubsub-general] javascript =
trick redux

--=20
I'd be interested in reviewing your .NET server if you'd care to share =
it.

I quickly whipped this out to try understand the reference to a =
continuous <script> file and it appeared to work fairly well. Of course =
IIS and .NET timed out which would negate the use of this combination of =
server tech unless this limitation could be circumvented.

But check it out - I assume this is similiar to what KN is doing...

http://www.bangeye.com/pubsub/


Dave Cline
[email protected]
www.bangeye.com/
801-636-5603




-----Original Message-----
From:     "Adam Rifkin" <[email protected]>
Sent:     Fri, 9 May 2003 19:32:09 -0700
To:       "Lucas Fletcher" =
<[email protected]>;<[email protected]>
Cc:       <[email protected]>
Subject:  [Mod-pubsub-developer] RE: [Mod-pubsub-general] javascript =
trick redux

Hi Lucas,

Browsers buffer data read off the wire.

To overcome this, try sending 4k or so of spaces after the </script> =
tag.

Also, we use hidden frames, not iframes.  Have a look at the kn_debug
part of the "Command-line Arguments" section in

   http://www.mod-pubsub.org/kn_docs/javascript_reference.html

or use ?kn_debug in the URL like so:

   http://www.mod-pubsub.org/kn_apps/presence1/?kn_debug

and this will reveal those hidden frames.

Hope that helps,
   Adam



-----Original Message-----
From: Lucas Fletcher [mailto:[email protected]]
Sent: Thursday, May 08, 2003 10:27 PM
To: [email protected]
Subject: [Mod-pubsub-general] javascript trick redux

Hello,

You thought you scared me away didn't you, with all your craziness and =
such?
Well it's not that easy I'm afraid.

I've spent the last day or so writing a server in .NET framework that =
keeps
open a javascript file like you guys are doing. My friend who is hosting
10's of thousands of flash-based clients (yeah, that's a custom server =
all
righty) says that the way to do it on Windows (he is using Linux) is =
with
I/O completion ports. His tests scaled up to at least a few thousands =
users
on one box. And I guess that the asynchronous methods in the
System.Net.Sockets namespace use I/O completion ports under the hood. =
This
uses the system thread pool for connection pooling. So I managed to =
write
the server with only a couple hundred lines of code. It uses a regular =
IIS
server for the upstream and then .NET remoting to communicate with the
custom server and then back down again via the javascript request. Which
brings me to a problem: the browser blocks execution on the javascript =
file
so the page doesn't load. Is there a special response header I need to
include? I can put the <script></script> tag after the closing <body> =
but I get some
weird errors elsewhere on the page, and also the IE world icon keeps
spinning. I noticed in the KnowNow demonstrations that this didn't =
happen.
Were there iframes being used? I covet its coolness.

--
Lucas Fletcher
[email protected]
http://dealersinnotions.com

_______________________________________________
Mod-pubsub
http://mod-pubsub.sf.net/




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