[Qgis-developer] [QGIS Server] How to share QgsPostgresSharedData between multiple QGIS instances

[Matthias Kuhn]

Hi Alessandro

> 
> In Lyon we also talked about how to share caches between different
> server processes, do you think that the shared memory segment would be
> appropriate in that case?

What are the caches used for?
I wouldn't exclude a shared-memory segment per-se but I also cannot say
it's THE solution. I'm not sure if there's a general answer to it.

Whatever it is, it needs to be properly protected against concurrent
access and possible deadlocks.

> For a cache it does not matter if it's not persistent.
> 
> The idea would be to have the server honour the 12 factors patterns.

I'm not familiar with it, but as far as I can tell, all requirements to
a cache are listed on the process page (https://12factor.net/processes)
which looks quite sensible to me.

Regards
Matthias