摘要:
A mechanism for data buffering is provided. A portion of a cache is allocated as buffer regions, and another portion of the cache is designated as random access memory (RAM). One of the buffer regions is assigned to a processor. A data block is stored to the one of the buffer regions of the cache according an instruction of the processor. The data block is stored from the one of the buffer regions of the cache to the memory.
摘要:
A system and computer implemented method for isolating errors in a computer system is provided. The method includes receiving a direct memory access (DMA) command to access a computer memory, a read response, or an interrupt; associating the DMA command to access the computer memory, the read response, or the interrupt with a stream identified by a stream identification (ID); detecting a memory error caused by the DMA command in the stream, the memory error resulting in stale data in the computer memory; and isolating the memory error in the stream associated with the stream ID from other streams associated with other stream IDs upon detecting the memory error.
摘要:
A mechanism for data buffering is provided. A portion of a cache is allocated as buffer regions, and another portion of the cache is designated as random access memory (RAM). One of the buffer regions is assigned to a processor. A data block is stored to the one of the buffer regions of the cache according an instruction of the processor. The data block is stored from the one of the buffer regions of the cache to the memory.
摘要:
A DDR SDRAM DIMM for a mainframe main storage subsystem has a plurality of DDR SDRAMs on a rectangular printed circuit board having a first side and a second side, a length (152 MM=6 inch) between 149 and 153 millimeters and optimized at 149.15 mm or 151.35 mm in length and first and second ends having a width smaller than the length; a first plurality of connector locations on the first side extending along a first edge of the board that extends the length of the board, a second plurality of connector locations of the second side extending on the first edge of the board, a locating key having its center positioned on the first edge and located between 80 mm and 86 mm and optimized with a locating key 1.5 mm wide centered at 81.58 or 85.67 mm from the first end of the board and located between 64 and 70 mm and optimized with the locating key centered at 67.58 or 65.675 from the second end of the board. Each DIMM has memory regions comprising one of a plurality of physical entities hereafter referred to as memory macros which are relocatable regions which contain SP Keys and data set storage in the DIMM physical memory. These memory macros SP Key regions define an arbitrary logic structure for main storage which has a hard physical boundary.
摘要:
A method to use of dual valid bit sets including a regular bit set and alternate valid bits set which prevents new requests to a given cache line from entering a multi-nodal computer systems' nest system until all requests to the given cache line have been completed successfully. By providing the alternate valid bits the dual set of resource valids for each remote requester is provided for each remote requester, where one set of valids indicates if the resource is valid and actively working on the line, and the other set of valids indicates if the resource was valid but encountered some conflict that requires resolution before the request can complete. Only on successful reload and completion of the remote operation does this alternate address valid bit reset and open the way for any pending interface requests to proceed, so all outstanding requests currently loaded in a local resource within the nest system are able to complete before new interface requests are allowed into the system.
摘要:
A method of ensuring system serialization in a multiprocessor multi-nodal environment is used to force all processors in a multiprocessor environment to temporarily suspend operations while one processor changes the system state. Architected designs where latencies between nodes are made known and predictable greatly simplify the task of coordinating quiesce responses within the system. When latencies are not fixed and topologies such as open or closed bus architectures are be used a more dynamic approach is required to ensure system serialization. Adaptive quiesce logic on each node's SCE can dynamically identify the role of the node within the system and automatically configure itself to guarantee that no enabled processor within the entire system receives a quiesce indication before all processors have reached the stopped state. This is also true for systems where nodes are being concurrently added or removed during system operation. Bus states process quiesce requests. Also this method of reaching a quiesced state operates independently of differing latencies between nodes. Defined master slave end and interior nodes are used within the quiesce network.
摘要:
A DDR SDRAM DIMM for a mainframe main storage subsystem has a plurality of DDR SDRAMs on a rectangular printed circuit board having a first side and a second side, a length (152 MM=6 inch) between 149 and 153 millimeters and optimized at 149.15 mm or 151.35 mm in length and first and second ends having a width smaller than the length; a first plurality of connector locations on the first side extending along a first edge of the board that extends the length of the board, a second plurality of connector locations of the second side extending on the first edge of the board, a locating key having its center positioned on the first edge and located between 80 mm and 86 mm and optimized with a locating key 1.5 mm wide centered at 81.58 or 85.67 mm from the first end of the board and located between 64 and 70 mm and optimized with the locating key centered at 67.58 or 65.675 from the second end of the board. Each DIMM has memory regions comprising one of a plurality of physical entities hereafter referred to as memory macros which are relocatable regions which contain SP Keys and data set storage in the DIMM physical memory. These memory macros SP Key regions define an arbitrary logic structure for main storage which has a hard physical boundary.
摘要:
Storage protection keys and system data share the same physical storage. The key region is dynamically relocatable by firmware. A Configuration Array is used to map the absolute address of the key region in to its physical address. The absolute address of keys can be fixed even though the physical location of the keys is relocated into a different region. A triple-etect double correct ECC scheme is used to protect keys. The ECC scheme is different from regular data in the storage and can be used to detect illegal access. Extra firmware and hardware is also designed to restrain customer's applications from directly accessing keys. With the key region being relocatable, the firmware could move the key region away from a known faulty area in a memory to improve system RAS. We also achieved the commonality objective that key memory device can use the same memory devices with other server systems that do not use keys.
摘要:
A shared memory symmetrical processing system including a plurality of nodes each having a system control element for routing internodal communications. A first ring and a second ring interconnect the plurality of nodes, wherein data in said first ring flows in opposite directions with respect to said second ring. A receiver receives a plurality of incoming messages via the first or second ring and merges a plurality of incoming message responses with a local outgoing message response to provide a merged response. Each of the plurality of nodes includes any combination of the following: at least one processor, cache memory, a plurality of I/O adapters, and main memory. The system control element includes a plurality of controllers for maintaining coherency in the system.
摘要:
Disclosed is an apparatus and means for searching a cache directory with full ECC support without the latency of the ECC logic on every directory search. The apparatus allows for bypassing the ECC logic in an attempt to search the directory. When a correctable error occurs which causes the search results to differ, a retry will occur with the corrected results used on the subsequent pass. This allows for the RAS characteristics of full ECC but the delay of the ECC path will only be experienced when a correctable error occurs, thus reducing average latency of the directory pipeline significantly. Disclosed is also a means for notifying the requester of a retry event and the ability to retry the search in the event that the directory is allowed to change between passes.