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Comment by Loic | Hacker News Reader

I am the author of this PaaS, I wanted to push this note on HN Monday to have time to answer the questions, but the cat escaped the box faster than I wanted. I am here to answer questions but do not expect "instant" answers.

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I built a very similar PaaS with mongrel2 about a year ago (though all applications were untrusted and running inside an OpenVZ container) - only to change it to be nginx/HTTP-based because of stability.

Great to see this technology is ready nowadays and can be used for production systems :)

Mongrel2 is still beta, but with a good process supervisor, it still way more robust than a RoR setup from the early days. Once in a while, it can die, I still need to instrument a bit more to track the conditions where this is the case.

On the other hand, ZMQ for the backend is just a pure pleasure and I haven't had a single failure of my components for more than 1 million real requests involving many ZMQ backend interactions.

Interesting, my problems back then were actually ZMQ-related.

Though to be fair, we were making it a bit complicated by suspending/resuming the OpenVZ containers. From that we sometimes got dead ZMQ connections that were black holing all traffic (incredibly hard to debug - ended up switching because of it).

Yes, most of my crashes on the mongrel2 server I run come from ZeroMQ too. They fix them when I find them, but I actually run my servers under valgrind continually so I can catch them and report them.

OpenVZ is tricky, they are patching the kernel pretty deep and this creates a lot of hard to debug issues. I had a lot of troubles with containers running software mapping big files like MongoDB.

Very nice post, thanks! I'm looking at experimenting with Mongrel2 to see if it would be a nice fit at work, where we still use apache2/mod_wsgi (we have modest needs) to interface our Python + CouchDB app. However, we've started adding WebSockets stuff to the system, and it would be nice to run everything in a slightly more coherent matter. We also use ZeroMQ to pump messages around the network (that later get converted into WebSockets frames for web frontend consumption).

- Is mongrel2 getting good development? The latest release was in June, and the latest commit in the canonical repo seems to be from July...

- Is there good support for RFC-version WebSockets yet?

- Is there easy/performant stuff for simple asset serving via mongrel2, or should I use nginx for that?

Hey, just a quick reply, that, yes I'm rather busy right now but I still squeeze in time for Mongrel2 and should be getting out a 1.8 beta soon.

1. Zed is coding in bursts, check the develop branch, it is pretty active and a 1.8 is around the corner.

2. The same, in the develop branch, there are still some questions on how to best implement it like which parts must be done by the handlers and which by Mongrel2, but the coders involved are good and very pragmatic, I bet the results will be a high quality implementation.

3. http://notes.ceondo.com is served by the "Dir" handler, that is, direct static files from disc without going through the asynchronous ZMQ based sequence. It is pretty fast.

Of note: There are several of us in #mongrel2 on Freenode, and there are periodic patches from us :).

I've been working on the WebSockets support. I changed the handler <-> mongrel2 interface for websockets a bit, and I think I've reached the right point in the websockets-devel branch. If you are interested in websockets you can check out that branch and see what you think. If I get no negative feedback I'm merging it into the develop branch once I've tested it more

Interesting username. Kind of reminds of me something... oh yeah, low orbit ion cannon, a DOS tool I have battled in the past.

Looking forward to your explanation.

My name is Loïc d'Anterroches. This relatively old, from disputed origin, French forename is not widely used. I can understand your reaction if reading my username brought memories of fighting against a DOS attack.

Wow, OK, sorry. I had no idea. Thanks for educating me.

I'm looking forward to your explanation of how you're posting from 10 AUs away from Earth.

It's also a popular French name (I know 2 Loics personally...) No idea why this particular user uses this username but, it might not be for the reasons you think...

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