Firebird (firebird) is an open-source Relational Database Management System (RDBMS). It is open source and free. It is powerful and easily managed.

Firebird runs on various systems. For example, Firebird 2.5 runs on Windows (32- and 64-bit), various Linux versions (32- and 64- bit), Solaris (Sparc and Intel), HP-UX (PA-RISC) and MacOS X.

With Firebird 2.1 and databases with ODS 11.1 (and higher) Firebird introduces the ability to monitor server-side activity happening inside a particular database.

Complete database monitoring is available to SYSDBA and the database owner. Regular users are restricted to the information about their own attachments only—other attachments are invisible to them.

Available monitoring tables since Firebird 2.1 and ODS 11.1:

• MON$DATABASE (connected database)
• MON$ATTACHMENTS (connected attachments)
• MON$TRANSACTIONS (started transactions)
• MON$STATEMENTS (prepared statements)
• MON$CALL_STACK (call stack of active PSQL requests)
• MON$IO_STATS (I/O statistics)
• MON$RECORD_STATS (record-level statistics)

Reference: Firebird 2.1 Release Notes

With Firebird 2.5 and databases with ODS 11.2 (and higher) Firebird adds the following new monitor tables

• MON$MEMORY_USAGE (current memory usage)
• MON$CONTEXT_VARIABLES (known context variables)

Reference: Firebird 2.5 Release Notes