[OSM-talk] Error when Exporting from Share icon

[Paul Norman]

On 1/26/2015 2:58 AM, Dave F. wrote:
> I don't know when it was last reviewed, but does this error have bit 
> of a sensitive trigger? Has the server that runs the process been 
> upgraded so it can handle a greater number of requests? If so, could 
> the error's cut in point be relaxed? 
The thresholds for each server have been adjusted multiple times and 
will probably continue to be so. Even if the load cutoff is increased 
there will be times when individual render requests are rejected for a 
few days in a row - stylesheet updates being the main one. It is 
considered more important to update the map rendering than to do a 
custom render. Personally I don't have many problems generating a custom 
render from osm.org, but I'm on a different timezone and keep different 
hours, which makes it hard to compare. I also get directed to a 
different server much of the time.



For the technical details, the render code relies on the system load 
average. This is not the best metric, a better one would be one of the 
renderd supplied queue sizes (e.g. don't do custom renders if anything 
is in the dropped queue) or to integrate it with renderd, but no one has 
stepped forwards to code this.

The reason why there's the restriction in the first place is that doing 
a custom render consumes 100x to 1000x the resources of a normal tile 
request.