Virtual topology discovery Computer Configuration

A computer implemented method for discovering topology information comprising information nested processors (CPUs) of a guest configuration in a computer system partitioned logically, the method comprising: searching (2001), by a processor guest configuration instruction STORE INFORMATION SYSTEM (store system information) for execution, the STORE SYSTEM INFORMATION instruction defined for a computer architecture; executing the instruction STORE SYSTEM INFORMATION, wherein said instruction STORE SYSTEM INFORMATION comprises a field opcode and a database field record, the field base registry to identify a location in memory of an information block system ( SYSIB); the characterized execution comprising: based on a request for topology information instruction STORE SYSTEM INFORMATION, obtaining (2004) topology information of the guest configuration wherein the topology information is configured to include a length of the SYSIB, and information of nested information nested comprising a hierarchical grouping of CPUs into containers according to proximity information nested comprising list entries topology (TLE) for each nesting level (NL), each TLE comprising an indicator (NL) nesting level, where the CPU specified by TLE CPU having NL = '0' and a hierarchy of nest structures which are specified by TLE containers having NL> '0' and store (2006) the topology information in the SYSIB in the memory location.