Update: An answer from the heavens descends! On the same day of my post, no less. Gotta love an active framework.
Like most of the Rails community, I’ve been swept up in the fascination lately over easier deployment via Passenger. After getting 2.2 deployed, I had hoped that Bonanzle could try to make the leap to Passenger and become yet another success story of a multi million monthly page viewed site proving that the hype behind Passenger is legit.
But then I remembered our Mongrel handlers, specifically, that said handlers are currently satisfying about 50% (or more) of the requests for our entire site (mostly through chat and instant message reads + posts). As such, upgrading to Phusion puts me ill at ease, because I would think that if our Mongrel handlers became standard Rails actions, we would 1) require twice as many Rails instances to run our site, possibly requiring more memory with Phusion instead of less and 2) incur a much greater overhead per request, when Rails runs its routing and other pricey (and in this case, unnecessary) default behaviors on our requests.
Normally I might pose this question to a forum, but given the esotericness of the problem, I suspect that such a question would assuredly be greeted with crickets. If anyone else has actually tried this, or seen any stories comparing the two, I’d love to hear them and post them to this blog to make it easier for others to find.
If all else fails, I plan to eventually setup a test case to actually benchmark and get some numbers, but that would figure to be at leeast a 1-2 day ordeal by the time sufficient reliable data could be gathered.