[Ur] Performance of Ur/Web in a live site

[Chris Double]

On Mon, Jun 13, 2011 at 6:37 AM, Adam Chlipala <adamc at impredicative.com> wrote:
> This is great news!  Is this application open source?  Would you mind saying
> which language/framework you used for the prior version?

The previous version was written using the Mozart/Oz programming
language, so nothing mainstream.

> Have you done any concurrency scaling performance comparison of the two
> versions?  Especially with Postgres as the database backend, I wouldn't be
> surprised if the Ur/Web version scales better, too, as you increase the
> number of threads (via the "-t" command-line parameter to the application).

Not yet but I will once I'm happy that it's stable. I plan to release
the source then too. I'm currently still working through a few issues,
only one of them Ur/Web based (the 401 authentication response - I'll
respond on the bug about that shortly). One part of the pool remains
written in Mozart/Oz. Pools provide a way of allowing clients to be
notified when certain events occur. They do this by providing a
'longpoll' URL that clients connect too. It's a long lived HTTP
request that the server sends data down when the event occurs. I
haven't implemented this in Ur/Web, I've left it in a seperate server
written in Mozart/Oz. Most of my issues have been related to scaling
the VPS it's running on (number of allowed open files per process,
nginx web server's number of workers/open files, etc).

Chris.
-- 
http://www.bluishcoder.co.nz