Date: Fri, 14 Apr 2006 11:46:10 -0400
Reply-To: Don Henderson <donaldjhenderson@HOTMAIL.COM>
Sender: "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From: Don Henderson <donaldjhenderson@HOTMAIL.COM>
Subject: Re: SAS application dispatcher maximum concurrent users
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The answer to your question of how many users can connect is impacted much
more by how long the SAS programs will take to run.
The misconception that CGI based applications are not suitable for large
numbers of users is very common - and very wrong when it comes to the
Application Dispatcher. I am writing a SAS Press book on the Application
Dispatcher and I discuss that issue in Chapter 3:
The Application Broker is a CGI program. CGI applications are quite often
broadly categorized as less than optimal due to the fact that the CGI
process must execute on the web server. For CGI applications that are "doing
all the work" this is a valid criticism. However the Application Broker is a
very lightweight application; it is doing very little work other than
communicating a request for services to another computer. Thus, the typical
criticisms of the Application Broker as a CGI program are often misplaced
(except in the case of rarely used Launch Services where all the work is
done on the web server since for Launch Services the SAS Application Server
is also running on the web server).
For heavily loaded systems where performance is critical, the reader may
want to consider one of the two additional versions (an ISAPI and a GWAPI
version) of the Application Broker that SAS has developed.
So your sizing issue is driven by how long the SAS programs that the
Application Dispatcher runs will take. I actually address that in my book as
well. I will try to send a snippet of that discussion later today. And while
I suspect I may regret it, I will also provide a link to one of the samples
for my book that uses a SAS/IntrNet Application Dispatcher program that runs
a queuing model to allow you to estimate how many Application Servers you
can expect to need. The reason I say that I might regret providing the link
is that the site is still a work in progress and I have not yet volume
tested it :-).
From: SAS(r) Discussion [mailto:SAS-L@LISTSERV.UGA.EDU] On Behalf Of Mehdi
Sent: Friday, April 14, 2006 10:05 AM
Subject: SAS application dispatcher maximum concurrent users
I want to know how many users can connect to sas using application
dispatcher ,simultaneously? as I've heard(I don't know where) the CGI base
internet applications are not suitable for big Projects?
any suggestion will be so helpful.