Abstract: A method for selecting a processor to be acquired in a virtual, shared computing environment includes initiating a first selection phase to attempt to acquire a last relinquished processor of the shared computing environment, and initiating a second selection phase in the event of a failure of the first selection phase in acquiring the last relinquished processor. The second selection phase further includes a round-robin selection process for presently relinquished processors.

Abstract: Method, system and program products for screening a program of a computing environment for debug processing are presented which employ a table that contains information identifying at least some program areas of storage of the computing environment where programs to be debugged may reside and information identifying programs of the computing environment to be excluded from debugging. After detecting a debug trigger point during execution of a program, screening is accomplished by referencing the table to first ascertain whether the trigger point is within a program area of storage meaning that the program under execution may comprise an application program to be debugged, and if so, referencing the table to determine whether the program has been explicitly excluded from the debug processing. If not excluded, debug processing may proceed.

Abstract: In a multiprocessing system, data which is stored on an external storage media and shared by a plurality of processors is converted from an old format to a new format without bringing the multiprocessing system down. One processor at a time is provided the capability to view the data in the new format, while the other processors view the data in the old format. After all of the processors are capable of viewing the data in the new format, the data is converted from the old format to the new format and the data in the new format is stored on the external storage media. If for some reason the new format turns out to be unacceptable, procedures are also in place for falling back to the old format without disrupting system availability.