On 2016-03-17 3:43, mailgroups@... [firebird-support] wrote:

> I had a strange coincidence today, but Im wondering if it actually
> may have been cause/effect instead.
>
> Im running fb_inet_server.exe 2.5.2.26539 on Windows 2008 Server.

You are running an old Firebird version that has a security bug in it
that can allow unauthenticated users to crash the server. I don't think
it has to do with the problem described below, but you should really
upgrade. Note that when upgrading you will need to backup and restore
your database to address a problem with indexes.

> Earlier today I created a simple "for select do update" stored
> procedure against a database that may have had 20-25 open connections
> from applicaiton servers/web servers. Compiling the stored proc
> seemed
> to take a very long time - I would have expected about 5 seconds, but
> it still hadnt finished after a couple of minutes.
>
> In the meantime I jumped on a couple of other tasks, and then started
> getting support calls from users that the applications were
> non-responsive. I saw that the DB usage had grown from the typical
> 1.5GB to 3.5GB, and was running at a steady 12% CPU. It stayed that
> way for a while, so I opened another copy of my DB management app and
> connected. I immediately tried to take a look at MON$STATEMENTS to
> see
> What was running, but the query never returned results. I could not
> connect to the DB after that, as even ISQL just hung when trying to
> start.
>
> After 30 minutes I had to reboot the server to bring the system back
> up, with hopefully no damage to the DB. There are no entries in
> Firebird.log that indicate what the original issue was, and sweeps
> that have occurred since seem normal.
>
> Im now wondering whether compiling that simple stored proc could have
> been the cause of all of this? I dont do major development during
> normal production hours, but I have certainly created or altered
> stored procedures many many times while this database was online
> without issue.

Is there anything in the firebird.log? It is hard to tell if it is a
known issue without a reproducible example. However a large number of
hangs and crashes were fixed since version 2.5.2, check the release
notes:
http://www.firebirdsql.org/file/documentation/release_notes/html/rlsnotes255.html.

Mark