Abstract: A method is provided for facilitating processing within a multiprocessor computer system by: setting, in association with invalidate page table entry processing, a storage key at a matching location in central storage of a multiprocessor computer system to a predefined value; and subsequently executing a request to update the storage key to a new storage key, the subsequently executing including determining whether the predefined value is an allowed stale value, and if so, replacing in central storage the storage key of predefined value with the new storage key without requiring purging or updating of the storage key in any local processor cache of the multiprocessor computer system, thus minimizing interprocessor communication pursuant to processing of the request to update the storage key to the new storage key.

Abstract: Processing within a multiprocessor computer system is facilitated by: setting, in association with invalidate page table entry processing, a storage key at a matching location in central storage of a multiprocessor computer system to a predefined value; and subsequently executing a request to update the storage key to a new storage key, the subsequently executing including determining whether the predefined value is an allowed stale value, and if so, replacing in central storage the storage key of predefined value with the new storage key without requiring purging or updating of the storage key in any local processor cache of the multiprocessor computer system, thus minimizing interprocessor communication pursuant to processing of the request to update the storage key to the new storage key.

Abstract: Processing within a multiprocessor computer system is facilitated by: logically clearing a data page by setting, in association with invalidate page table entry or set storage key processing, a page initialize bit for the data page to a clear data value without physically clearing data from the data page; and subsequent to the setting of the page initialize bit, physically clearing data from the page in central storage responsive to a first access to the page with the page initialize bit set to the clear data value, thereby minimizing overall time required to both clear and subsequently access cleared page data. Setting of the page initialize bit may include setting a line clear bit for each page line to the clear data value, and allocating a state machine to clear each line responsive to the line being first accessed with the its line clear bit set.

Abstract: Processing within a multiprocessor computer system is facilitated by: deciding by a processor, pursuant to processing of a request to update a previous storage key to a new storage key, whether to purge the previous storage key from, or update the previous storage key in, local processor cache of the multiprocessor computer system. The deciding includes comparing a bit value(s) of one or more required components of the previous storage key to respective predefined allowed stale value(s) for the required component(s), and leaving the previous storage key in local processor cache if the bit value(s) of the required component(s) in the previous storage key equals the respective predefined allowed stale value(s) for the required component(s). By selectively leaving the previous storage key in local processor cache, interprocessor communication pursuant to processing of the request to update the previous storage key to the new storage key is minimized.

Abstract: Processing within a multiprocessor computer system is facilitated by: deciding by a processor, pursuant to processing of a request to update a previous storage key to a new storage key, whether to purge the previous storage key from, or update the previous storage key in, local processor cache of the multiprocessor computer system. The deciding includes comparing a bit value(s) of one or more required components of the previous storage key to respective predefined allowed stale value(s) for the required component(s), and leaving the previous storage key in local processor cache if the bit value(s) of the required component(s) in the previous storage key equals the respective predefined allowed stale value(s) for the required component(s). By selectively leaving the previous storage key in local processor cache, interprocessor communication pursuant to processing of the request to update the previous storage key to the new storage key is minimized.

Abstract: A method is provided for facilitating processing within a multiprocessor computer system by: setting, in association with invalidate page table entry processing, a storage key at a matching location in central storage of a multiprocessor computer system to a predefined value; and subsequently executing a request to update the storage key to a new storage key, the subsequently executing including determining whether the predefined value is an allowed stale value, and if so, replacing in central storage the storage key of predefined value with the new storage key without requiring purging or updating of the storage key in any local processor cache of the multiprocessor computer system, thus minimizing interprocessor communication pursuant to processing of the request to update the storage key to the new storage key.

Abstract: Processing within a multiprocessor computer system is facilitated by: deciding by a processor, pursuant to processing of a request to update a previous storage key to a new storage key, whether to purge the previous storage key from, or update the previous storage key in, local processor cache of the multiprocessor computer system. The deciding includes comparing a bit value(s) of one or more required components of the previous storage key to respective predefined allowed stale value(s) for the required component(s), and leaving the previous storage key in local processor cache if the bit value(s) of the required component(s) in the previous storage key equals the respective predefined allowed stale value(s) for the required component(s). By selectively leaving the previous storage key in local processor cache, interprocessor communication pursuant to processing of the request to update the previous storage key to the new storage key is minimized.

Abstract: Processing within a multiprocessor computer system is facilitated by: setting, in association with invalidate page table entry processing, a storage key at a matching location in central storage of a multiprocessor computer system to a predefined value; and subsequently executing a request to update the storage key to a new storage key, the subsequently executing including determining whether the predefined value is an allowed stale value, and if so, replacing in central storage the storage key of predefined value with the new storage key without requiring purging or updating of the storage key in any local processor cache of the multiprocessor computer system, thus minimizing interprocessor communication pursuant to processing of the request to update the storage key to the new storage key.

Abstract: Processing within a multiprocessor computer system is facilitated by: logically clearing a data page by setting, in association with invalidate page table entry or set storage key processing, a page initialize bit for the data page to a clear data value without physically clearing data from the data page; and subsequent to the setting of the page initialize bit, physically clearing data from the page in central storage responsive to a first access to the page with the page initialize bit set to the clear data value, thereby minimizing overall time required to both clear and subsequently access cleared page data. Setting of the page initialize bit may include setting a line clear bit for each page line to the clear data value, and allocating a state machine to clear each line responsive to the line being first accessed with the its line clear bit set.

Abstract: Processing within a multiprocessor computer system is facilitated by: deciding by a processor, pursuant to processing of a request to update a previous storage key to a new storage key, whether to purge the previous storage key from, or update the previous storage key in, local processor cache of the multiprocessor computer system. The deciding includes comparing a bit value(s) of one or more required components of the previous storage key to respective predefined allowed stale value(s) for the required component(s), and leaving the previous storage key in local processor cache if the bit value(s) of the required component(s) in the previous storage key equals the respective predefined allowed stale value(s) for the required component(s). By selectively leaving the previous storage key in local processor cache, interprocessor communication pursuant to processing of the request to update the previous storage key to the new storage key is minimized.

Abstract: A method and system of storing to an instruction stream with a multiprocessor or multiple-address-space system is disclosed. A central processing unit may cache instructions in a cache from a page of primary code stored in a memory storage unit. The central processing unit may execute cached instructions from the cache until a serialization operation is executed. The central processing unit may check in a message queue for a notification message indicating potential storing to the page. If the notification message is present in the message queue, cached instructions from the page are invalidated.

Abstract: A method and system of storing to an instruction stream with a multiprocessor or multiple-address-space system is disclosed. A central processing unit may cache instructions in a cache from a page of primary code stored in a memory storage unit. The central processing unit may execute cached instructions from the cache until a serialization operation is executed. The central processing unit may check in a message queue for a notification message indicating potential storing to the page. If the notification message is present in the message queue, cached instructions from the page are invalidated.

Abstract: A method and system of organizing a cache memory system based on a temporal-access pattern is disclosed. One or more data entries may be stored in a memory. One or more cache entries of the one or more data entries may be stored in a temporal cache. The one or more cache entries may be physically organized based on a temporal access pattern. A cache entry of the one or more cache entries may be based upon a condition.

Abstract: A method and system of storing to an instruction stream with a multiprocessor or multiple-address-space system is disclosed. A central processing unit may cache instructions in a cache from a page of primary code stored in a memory storage unit. The central processing unit may execute cached instructions from the cache until a serialization operation is executed. The central processing unit may check in a message queue for a notification message indicating potential storing to the page. If the notification message is present in the message queue, cached instructions from the page are invalidated.

Abstract: A method and system of organizing a cache memory system based on a temporal-access pattern is disclosed. One or more data entries may be stored in a memory. One or more cache entries of the one or more data entries may be stored in a temporal cache. The one or more cache entries may be physically organized based on a temporal access pattern.

Abstract: A method and system of storing to an instruction stream with a multiprocessor or multiple-address-space system is disclosed. A central processing unit may cache instructions in a cache from a page of primary code stored in a memory storage unit. The central processing unit may execute cached instructions from the cache until a serialization operation is executed. The central processing unit may check in a message queue for a notification message indicating potential storing to the page. If the notification message is present in the message queue, cached instructions from the page are invalidated.

Abstract: A clock distribution system for reducing clock skew between tightly coupled central processing units in a multi-processor system. The multi-processor system includes (1) a configuration processor for generating a first configuration signal and a second configuration signal, a first clock, a second clock, (2) a first processor having a first central processing unit, (3) a second processor having a second central processing unit, (4) a first clock generator for generating a first delayed clock signal from the first or second clock in accordance with the configuration signals, and (6) a second clock generator generating a second delayed clock signal from the first or second clock in accordance with said configuration signals.

Abstract: To verify proper interconnection of an interconnect network, a transitory test signal is introduced at a first node of a network within a system under test. A search is made of all other system nodes for responsive transitions. A comparison is made between the addresses of nodes where transitions are observed within a predetermined time span and the addresses of nodes where transitions are expected. The predetermined time span is adjusted to detect missing or miswired line-conditioning components.

Abstract: A computer system architecture implementing multiple central processing units, each including a split instruction and operand cache, and that provides for the management of multiple copies (line pairs) of a memory line through the use of a line pair state is described. Systematic management of memory lines when transferred with respect to instruction and operand data cache memories allows the integrity of the system to be maintained at all times. The split cache architecture management determines whether a memory line having a first predetermined system address is present within both the instruction and operand cache memories or will be upon move-in of a memory line. Address tag line pair state information is maintained to allow determinations of whether and where the respective memory line pair members reside. The architecture implements the management of the line pairs on each transfer of a memory line to any of the split caches of the system.

Abstract: The reporting of errors that are detected when data which contains an error is moved from a high speed buffer memory array to a main storage array is deferred so that the error checking and correcting logic associated with the main storage memory array will recognize the data as containing an error generated in the buffer array and report the error only when the data is moved out of the main store. In this manner, a process relevant to the erroneous data is assured to be in operation when the error is reported.