Performance of routines with 32-bit libraries on 64-bit database servers

It is possible to call routines with 32-bit routine libraries on 64-bit database servers. However, this does not perform as well as calling a 64-bit routine on a 64-bit server.

The reason for the performance degradation is that before each attempt to execute a 32-bit routine on a 64-bit server, an attempt is first made to call it as a 64-bit library. If this fails, the library is then called as a 32-bit library. A failed attempt to call a 32-bit library as a 64-bit library produces an error message (SQLCODE -444) in the database diagnostic file (db2diag.log).

Java™ classes are bit-width independent. Only Java virtual machines (JVMs) are classified as 32-bit or 64-bit. The database manager only supports the use of JVM that is the same bit width as the instance in which they are used. In other words, in a 32-bit database instance only a 32-bit JVM can be used, and in a 64-bit database instance only a 64-bit JVM can be used. This ensures proper functioning of Java routines and the best possible performance.