Re: IceBreak as an alternative to Apache?

[Joe Pluta <joepluta@xxxxxxxxxxxxxxxxx>]

On 12/31/2010 2:38 PM, Aaron Bartell wrote:
> I am not sure what the max clients is, but I do know that when I have done
> testing with JMeter I hit the TCP layer bottleneck before I hit the OS job
> limitation.  Actually, that was a test for stateless transactions.  I
> basically spun up a couple hundred Apache jobs and hit it hard with JMeter.
>   That's when things started falling apart and I had to call IBM.  They of
> course told me it was my software, so I had to put together a bare bones CGI
> app and prove it wasn't.  Then they got one of the higher level devs on and
> they pretty much determined it was at the TCP layer.  You can adjust the TCP
> layer settings, but they recommended against it.

The number I've seen in the literature is 256.  That's the default 
number and you need to do some finagling to increase that number.  This 
seems to correspond to what you're saying - a couple of hundred jobs and 
things go casters up.  What happens, of course, is that requests get 
"queued" but it depends on the browser side whether or not that queuing 
gets handled gracefully.  Too long a wait and the browser's going to choke.

> I know a million connections is a lot, but I am dreaming big for some social
> media type applications I have up my sleeve :-)  I guess if I ever did get
> over a couple thousand concurrent connections that I would want to have
> multiple servers at different geographic locations because it would probably
> mean I hit the jackpot! ;-)

Exactly.  At that point you start to consider scaling horizontally.  You 
might want to have a front end that handles the requests and calls the 
back end.  This is also a good idea to deal with DDOS attacks (just in 
case you get on the bad side of Wikileaks <grin>).  Seriously, though, 
if you can design your application so that you have a very thin UI layer 
you can scale out to lots of UI servers which all feed back to one 
business logic server.  It's a pretty solid architecture.

Joe