[avahi] limit on dbus client objects

[Brian Gerkey]

On Oct 11, 2007, at 5:02 PM, Lennart Poettering wrote:

> On Thu, 04.10.07 10:13, Brian Gerkey (brian at gerkey.org) wrote:
>
>> - Independent of the Zeroconf implementation that's being used, are
>> there drawbacks in general to registering and browsing large numbers
>> of services?
>
> Yes. They cost resources, mostly in network traffic. The less you have
> the less traffic is generated.
>
> May I ask you to elaborate a little why you need so many services per
> client?

I'm adding service discovery to the Player robot device server, part  
of the Player Project (http://playerstage.sf.net), which I maintain.   
Each robot will advertise a handful of services (usually sensors,  
like lasers and cameras), so with real robots the resource limits are  
not a big deal: a few services per machine.  But when working in  
simulation, I might have hundreds of simulated robots on a single  
machine, in a single process.

I'd like to use the same service discovery scheme with real and  
simulated robots, so I need to resolve this service discovery  
resource issue somehow.  Any advice?  I could save a bit by bundling  
each robot's sensors into a single service per robot, but that won't  
be enough.  I could save a lot by bundling all the (simulated) robots  
controlled by a single process into a single service.  But then I  
have to implement a second-tier discovery mechanism to drill down  
inside each monolithic service to find out exactly what it's offering.

	brian.