Re: [Gnumed-devel] choice of web frameworks

[Karsten Hilbert]

On Tue, Jul 13, 2010 at 08:30:06AM +0200, Hilbert, Sebastian wrote:

> > merging this with SimpleJSONRPCServer.py, and adding in a persistent
> > psycopg connection into the "client", this would be ready to use _now_.
> > 
> > but, you would only be able to use about 2 clients because of the pool
> > limiting on the gmPG2 code.
> 
> I have to find out what that limit actually means. If I got that right it 
> means this that for each client we would need to open one connection. All 
> calls to the database would then however be pooled through the gmPG pooling 
> of 
> that client or do we still have to open one connection per request ?

gmPG2 creates connections upon request.

It will pre-open one read-only connection per thread. They
are handed out again and again as needed.

It will open a new read-write connection on each write
request.

Currently GNUmed uses up to three threads:

- the main one in which the GUI is executed

- one for the database signal listener

- one for the XML-RPC scripting API if so configured

> Since we support more then one fat client (each haaving its own connection) I 
> guess serving 10 clients (10 connections) should not be a problem.

Not at all.

> That still does not solve the problem that clients could open up threads and 
> bring down the server, doesn't it ? Is there some sort of keepalive 
> mechanism. 

PostgreSQL 9.0 eventually built keepalive into libpq.

Karsten
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