Hercules Version 3: Configuration File
Posted in Hercules Soft on June 3, 2002
The configuration file hercules.cnf contains the processor and device layout. It is roughly equivalent to the IOCDS on a real System/390. The configuration file is an ASCII text file.
System parameters may appear in any order but they must precede all device records. Each system parameter must be on a separate line.
Multiprocessor emulation is only available when the definition of the compile-time variable MAX_CPU_ENGINES in the file config.h has a value of more than 1. Current versions of Hercules already have this value set to 2 by default, so all you need to do is specify NUMCPU 2 in your configuration file. If you wish to define a greater value for MAX_CPU_ENGINES, use the --enable-multi-cpu=NUMBER option when you do your ./configure before doing your make.
Multiprocessor emulation works best if your host system actually has more than one physical CPU, but you can still emulate multiple CPUs nervertheless even on a uniprocessor system (and you might even achieve a small performance benefit when you do). There is little point, however, in specifying NUMCPU greater than 1 unless your guest operating system (running under Hercules) is actually able to support multiple CPUs (and if you do not actually need multiprocessor emulation, then setting MAX_CPU_ENGINES to 1 at compile time might even produce a slight performance advantage too).