> -----Original Message-----
> From: Kevin Duffey [mailto:[EMAIL PROTECTED]]
> Sent: Thursday, April 06, 2000 7:03 PM
> To: [EMAIL PROTECTED]
> Subject: Re: HttpSession object and scalability?
> ask. It seems
> odd to me that EJB, which I thought was partly being used to
> store sessions
> (hence session beans) is much slower than using HttpSession
> to store session
> state. I would love for someone to explain exactly why a
> session bean is
First, differentiate between stateful and stateless session beans. Stateless
session beans are shared at the method level, so a bean can service other
requests during browser latency (user reading, etc.), so you get more bang
for your bean.
> Also, on that note, I also ask, is the HttpSession and
> web-server stuff
> (servlets, action classes, javabeans, jsp, etc) scalable
> where you can add a
> second web-server or more to handle more incoming requests,
> as well as can
> two or more servers use the n-tier EJB servers properly? How
> does everything
> stay in sync so that a 2nd web server that calls a 4th ejb
> server knows to
> always send its requests to that 4th server, and how does the incoming
> request for that session always know to go to the second web
> server so that
> it can make sure it submits to the 4th ejb server?
Not sure about your use of n-tier here, but if I understand your question I
guess this would be implementation specific. For example, Weblogic can be
clustered and the key to each session is normally stored as a cookie. State
information is stored on a failover server in case the primary server fails.
If the primary fails the secondary is promoted to primary and another
secondary is created. I think the ip address of the primary is stored in the
cookie so that would be how the correct server is referenced on the next
request. Alternatively, URL rewriting or hidden variable may be used.
Cheers,
Jim
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