Backend design advice

[fr33domlover <fr33domlover mailoo org>]

Hello,

This question is quite general but I'd like to know how things in GNOME 
were designed, in addition to any general advice you have.

Assume a GUI application uses a central data backend, e.g. Tracker. 
Currently Tracker is a single central storage service, i.e. one daemon 
accepting connection and queries from apps.

Now assume I want to have more than one database: for example a 
separate database for some project I work on, a separate database for 
documenting file system hierarchy, separate database for desktop items, 
etc. The common approach, at least in SQL, is to have a single entry 
point, an SQL server, which handles all the databases stored on the 
computer. All clients connect to the same server.

Here's another possible approach: If the number of databases is small, 
it may be reasonable to launch a separate server for each database, and 
have them communicate with each other through IPC. There would 
probablly need to be another service to route network traffic to the 
right server, but aside from that, each database would have its own 
server (daemon) handling access to it.

Would the second approach be better at anything? Is it something people 
do, something reasonable? Or the approach of a single server per 
computer is clearly better?

(Would the second approach be more safe or scalable or resilient etc.)

By the way launching separate threads for queries or separate databases 
still counts as having a single server


- f