Method and system for controlling/monitoring computer system having plural operating systems to run thereon

A computer system dedicated to accumulation of trace data which can execute a plurality of operating systems traced during, comprising:

• an instruction processor for executing processings of said operating systems under control of a control program;
• a real main storage including a first area assigned to said control program and having a first trace area for storing trace information and a second area assigned to at least a part of a virtual main storage which is used as a main storage by said operating systems, said virtual main storage including a second trace area for storing trace information;
• external storage means for storing data held by said virtual main storage;
• indicating means for indicating at least one event selected from the group consisting of:
• (a) an event indicating that successful branching has resulted from execution of a branch instruction resident at an area of the virtual main storage designated by a running operating system,
• (b) an event indicating that an instruction resident at an area of the virtual main storage designated by a running operating system has been executed,
• (c) an event indicating that data have been stored at an area of the virtual main storage designated by a running operating system, and
• (d) an event indicating that a general register designated by a running operating system is updated or altered by an instruction resident at an area of the virtual main storage designated by the running operating system;
• and
• debugging means for detecting execution of a particular program event designated previously by said operating system and for storing trace information in said real main storage based on an address provided from said instruction processor in response to a result of detection;
• wherein said instruction processor comprises:
• a first register for holding an address indicating a location of trace information in said first trace area on said real main storage,
• a second register for holding an address indicating a location of trace information in said second trace area on said virtual main storage used by a running operating system,
• address translation means for translating an address held in said second register to a corresponding address on said real main storage,
• determining means for determining whether said second trace area indicated by an address held in said second register resides in said second area assigned to a running operating system or not, and
• means responsive to a result of determination by said determining means for selecting an address held in said first register in case of negative result and an address provided from said address translation means in case of affirmative result and outputting said selected address to said debugging means as a trace area address.