[OSM-dev] mod_tile PID file

[Paul Norman]

> From: Troy Wu [mailto:troywu at yahoo.com]
> Sent: Tuesday, April 01, 2014 5:20 PM
> To: dev at openstreetmap.org
> Subject: [OSM-dev] mod_tile PID file
> 
> Howdy, all.
> 
> New here.  Just built an OSM tile-server "manually" against Ubuntu 12.04
> LTS, and wanted to have multiple rendering pipelines.  It wasn't hard to
> get a virtual-hosts setup running to have multiple apache ports.
> Obviously, the trick was to get multiple renderd's running.  
> 
> [... technical details ...]
> 
> This is obviously clunky.  Still, it seems like having multiple
> rendering pipelines per PostGIS instance is something that some people
> would like to have.  It also seems like an obvious use of a datasource,
> since so much of the in deploying a tile server is getting the database
> up, imported, and kept-up-to-date.  Of course, I suppose it's possible
> to run separate servers (which in a Xen/KVM environment might make
> sense), and keep things clean.  OTOH, if someone is just experimenting
> with one server, it doesn't seem unreasonable.
> 
> I'd appreciate hearing thoughts on this.

The standard way to do this would be to run one copy of renderd, and 
specify multiple stylesheets in the configuration file. This removes 
the need to run multiple copies of apache or renderd.