[Mongrel] Automatic Scaling

[Jeremy Wilkins]

Hi,

I've got an app which will only be dealing with a few requests a  
minute for most of the time, then will shoot up to a continuous 20  
req/s for an hour at a time. We'll potentially be running a lot of  
instances of this app on the same server.

Is there any way to have additional instances of Mongrel be started  
when the existing instance(s) stopping being able to handle the  
volume of traffic. I could preload adequate instances to cope with  
peak traffic but that will result in a lot of instances sitting idle  
for the majority of the time.

Does anyone have any experience of SCGI? I know that FastCGI will  
start loading additional app instances after a certain threshold -  
does SCGI behave the same.

Thanks

Jeremy