Re: something more about my question about performance

From: "Enrico Mangano" <enrico.mangano@nethouse.it>

> I wrote :
> >Hello,
> >i have one postgresql server (7.0) where several users access.
> >Is there any way to improve performance for:
> >
> >i)  accesses of different users at different dbs
> >ii) accesses of different users at the same db
> >
> >Thanks.
>
> My question simple wanted know if it is possible, to improve
> performance, to make
> users access to different postgres servers, making access, for example,
> the user1 to the db1
> on the server1, the user2 to db2 on the server2 and so on. If it
> possible, how can I do that?

Ah - that makes a little more sense. Obviously you can have different
databases on different machines, but I presume you want the users to just
access one name:

user1 connects to dbserver->database1 which goes to machine1
user2 connects to dbserver->database2 which goes to machine2

Good idea - means you can rearrange things at the backend without having to
concern the users.

There's no way to do this "out of the box" but if you have some control over
the clients then you could try the following:

1. Write a small wrapper to psql that scans the command-line parameters and
pulls out the database name.
2. This either checks a local file or talks to a control server that picks
the correct backend machine.
3. The wrapper then launches psql with all the provided parameters and the
hostname fetched.

Result: user is connected to the relevant machine without having to know
which it is.

You could do something similar with perl/php/java connect procedures.

If you want one database spread over several machines then you will need to
look at the replication in /contrib in 7.1, but I can't tell you whether
that would work in your case.

Tom - sorry to bother you but this sounds like the sort of thing that might
be handled by the front<->postmaster protocol on startup (returns a
ReconnectTo packet). Would this be a generally useful thing for people, if
so has it been done, if it hasn't is it a good place for a newbie to get
used to the code? (it does sound like I'm volunteering doesn't it?)

- Richard Huxton