Abstract: A central processor uses virtual addresses to access data via cache logic including a DAT and ART, and the cache logic accesses data in the hierarchical storage subsystem using absolute addresses to access data, a part of the first level of the cache memory includes a translator for virtual or real addresses to absolute addresses. When requests are sent for a data fetch and the requested data are not resident in the first level of cache the request for data is delayed and may be forwarded to a lower level of said hierarchical memory, and a delayed request may result in cancellation of any process during a delayed request that has the ability to send back an exception. A delayed request may be rescinded if the central processor has reached an interruptible stage in its pipeline logic at which point, a false exception is forced clearing all I the wait states while the central processor ignores the false exception.

Abstract: A pipelined multiprocessor system for ESA/390 operations which executes a simple instruction set in a hardware controlled execution unit and executes a complex instruction set in a milli-mode architected state with a millicode sequence of simple instructions in the hardware controlled execution unit, comprising a plurality of CPU processors each of which is part of said multiprocessing system and capable of generating and responding to a quiesce request, and controls for system operations which allow the CPUs in the ESA/390 system to process the local buffer update portion of IPTE and SSKE operations without waiting for all other processors to reach an interruptible point, and then to continue program execution with minor temporary restrictions on operations until the IPTE or SSKE operation is globally completed. In addition, Licensed Internal Code (LIC) sequences are defined which allow these IPTE and SSKE operations to co-exist with other operations which require conventional system quiescing (i.e.

Abstract: A pipelined multiprocessor system for ESA/390 operations which executes a simple instruction set in a hardware controlled execution unit and executes a complex instruction set in a milli-mode architected state with a millicode sequence of simple instructions in the hardware controlled execution unit, comprising a plurality of CPU processors each of which is part of said multiprocessing system and capable of generating and responding to a quiesce request, and controls for system operations which allow the CPUs in the ESA/390 system to process the local buffer update portion of IPTE and SSKE operations without waiting for all other processors to reach an interruptible point, and then to continue program execution with minor temporary restrictions on operations until the IPTE or SSKE operation is globally completed. In addition, Licensed Internal Code (LIC) sequences are defined which allow these IPTE and SSKE operations to co-exist with other operations which require conventional system quiescing (i.e.

Abstract: A computer for executing programs and having a structure for fetching instructions and/or operands along a path which may not be taken by a process being executed by a computer processor having a hierarchical memory structure with data being loaded into cache lines of a cache in the structure, and having block line fetch signal selection logic and computational logic with hedge selection logic for generating line fetch block signals for control of hedging by fetching instructions and/or operands along a path which may not be taken by a process being executed and making selected hedge fetches sensitive to whether the data is in the cache so as to gain the best performance advantage with a selected hedge fetch signal which accompanies each fetch request to the cache to identify whether a line should be loaded if it misses the cache to indicate a selected hedge fetch when this signal is ON, and rejecting a fetch request in the event the selected hedge fetch signal is turned ON if the data is not in the cache, th

Abstract: A computer for executing programs and having a structure for fetching instructions and/or operands along a path which may not be taken by a process being executed by a computer processor having a hierarchical memory structure with data being loaded into cache lines of a cache in the structure, and having block line fetch signal selection logic and computational logic with hedge selection logic for generating line fetch block signals for control of hedging by fetching instructions and/or operands along a path which may not be taken by a process being executed and making selected hedge fetches sensitive to whether the data is in the cache so as to gain the best performance advantage with a selected hedge fetch signal which accompanies each fetch request to the cache to identify whether a line should be loaded if it misses the cache to indicate a selected hedge fetch when this signal is ON, and rejecting a fetch request in the event the selected hedge fetch signal is turned ON if the data is not in the cache, th