At 11:42 AM 3/02/2009, you wrote:

>We have a pool of more than 600 users accessing some FB 2.1.1
>databases on a Open SUSE Linux server from different win32 apps
>(Delphi 7 and VB6).

Superserver?

>We have migrated those databases from FB 1.5 since there was a
>performance problem with large DB sql queries and stored procedures
>(one of this DBs has a single file of more than 9 GB with a table of
>more than 25 millions of records).
>After the migration, the server begins with random crashes
>("terminated abnormally (-1)" message on firebird.log).
>Unfortunatelly, this log is not enough to detect what is the problem.
>After some surfing through several forums we detected that problems
>could be among:
>1) incompatibility of clients (gds32.dll, fbclient.dll, etc.)

No

>2) incompatibility of UDFs (i.e.: rfunc)

Yes

>3) Network disconnection of some clients (errors 104, 32, etc. in the
>log).

No - these are symptoms, not causes

>4) Incompatibility of components used in the source code (Zeos,
>Intersol, IProvider, etc.)

No

>5) Queries that are restricted from FB 2.0 (table alias, etc.)

No. Exceptions, yes.

>6) Linux rights over some files or folders? (errors while writing to
>FDB datafiles).

No. If permissions were the problem, it wouldn't cause random crashes. It just wouldn't work.

>7) Any other I forget?

Assuming Superserver (because of the Guardian message you're seeing in the log)

8) OS threading model. You'll get "random crashes" if

a) you're trying to use the NPTL package on a Linux where NTPL is broken.
b) you're trying to use the non-NPTL package on a Linux where NPTL is the active threading model.

9) You're getting an out-of-memory condition under load with 600 users threading off one Superserver process.

10) You are running some admin tool alongside regular user applications, that is keeping a MON$ transaction running and consuming resources

./heLen