Subject Re: [Firebird-Java] Re: Is there a limit of connections?
Author Helen Borrie
At 10:13 AM 29/04/2004 +0300, you wrote:
>I can remember an old thread in firebird-users list and some one stated
>that firebird have hardcoded limit of 1024 connections.

That is the theoretical limit for TCP/IP. The theoretical limit is lower
for Windows named pipes ("NetBEUI") – the server is likely to hang at more
than 930 concurrent connections.
As a practical guideline, work on a base maximum of about 150 concurrent
Superserver clients for a normal interactive application on a server of
low-to-medium specification, with low-to-moderate contention, before
performance might make you consider upgrading (and this is without taking
the needs of the JVM into account). For Classic, the numbers may be lower
because each client consumes more resources.

About the one thing you can be certain about is that there is *no
certainty*, even if you think you've got it right by adding up
numbers. Every user connection drains resources that the database server
could otherwise use. Database servers love memory. There will always be
some critical point at which the number of connected users is using more
resources than the database engine can spare. In other words, there are
theoretical limits and there are practical limits. Only proper reality
testing can get you the right answer for your site.