Informix Tech Notes article on SMI and the Sysmaster Database (PDF)

Published on September 8, 1999 by Lester Knutsen

First published in the Informix Tech Notes Magazine in 1999


When you list all of the databases on your Informix server, you will see one called “sysmaster”. This special database, which first appeared in Informix’s 6.x and 7.x servers, contains system monitoring interface (SMI) tables that can be used for monitoring your system. In this article, we will explore some of the tables and views that are in the sysmaster database.

The sysmaster database is described as a pseudo-database, meaning that most of its tables are not normal tables on disk, but pointers to shared memory structures in the database engine. The sysmaster database con- tains over 120 tables. Only 18 of these tables are documented in the INFORMIX-OnLine Dynamic Server Administrator’s Guide, Volume 2, Chapter 38. The rest are undocumented, and described by Informix as for internal use. The examples and references in this article are based on Informix Dynamic Server version 7.23. I have also tested some of the examples with versions 7.10, 7.12, and 7.22. There are some minor changes between versions in the undocumented features and structures of these tables.