Subject Classic Server User Limit
Author dr_john_mp
We have just upgraded from 2.0.0 to 2.0.1 and took the opportunity to
switch to Classic Server as we have 30+ users most of whom will run
more than one database application.

We have been running 2.0.0 classic on our development server for some
time so were reasonably confident - both the development and live
servers run Linux

As the users built up we rapidly got into a situation where
connections were failing, with approx 28 active instances of the

We obviously need to look at some of the parameters of the lock
manager and cache sizes - to avoid downtime we have installed 2.0.1
Superserver so have a bit of time to sort things out.

However we were left with some questions

Is there a way to identify the cause of the limitation - we didn't
appear to get any errors in the Firebird log as I would have expected.

In Classic how do you forcefully stop and restart the server, without
individually killing every instance. Asking every user to log out
isn't always practical, and they don't always respond.

How do you identify the number and names of current active users.
Firebird creates a new instance for every connection, but with itself
as the user. Programs like IBExpert will list/manage allowable users
but in Classic only show itself as an active user (ie it only sees
users in its own instance), as does a Delphi program using
TIBSatisticalService. Most of our own applications write a status
report to a 'RUNNING' table (eg with their oldest current transaction)
but that doesn't track 'standard' applications.