Philippe Ferreira <phil.f at worldonline.fr> writes:
>>1.  slon processes = 50 clusters x 2 nodes = 100 processes
>>
>>There will be... hmmm...  I think... 4 threads apiece, so the process
>>table would report 400 slon processes
>>
>> 2.  Each of those threads will open at least one database
>> connection. Those servicing subscriptions (there will be 50 of
>> these) will open two
>>connections.
>>
>>That would mean 450 connections, ergo 450 postmaster backends.
>>
>>Unfortunately, yes, that will add up to rather a lot of processes :-(
>>
>>
> Hi,
>
> I think it will be worse, because each server would host a total of
> 100 databases (50 "master"
> + 50 "slave" databases) :
>  - Server "A" will be the master node for 50 databases, and "B" their
> slave node.
>  - Server "B" will be the master node for 50 other databases, and "A"
> their slave node.

That pretty well doubles each number...

> Do you think it's a viable setup ?

Probably not.

A way around this "explosion" of replication management would be to
join databases together.

Rather than having 50 databases, each with one schema/namespace, you
might put them into one database with 50 schemas/namespaces.  That
would not require many clusters/slon processes.
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Christopher Browne
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