摘要:
A technique to share cache lines among a plurality of bus agents. Embodiments of the invention comprise at least one technique to allow a number of agents, such as a processor or software program being executed by a processor, within a computer system or computer network to access a locked (“owned”) cache line, under certain circumstances, without incurring as much of the operational overhead and resulting performance degradation of many prior art techniques.
摘要:
Systems and methods are disclosed for interaction between different cache coherency protocols. One system may comprise a home node that receives a request for data from a first node in a first cache coherency protocol. A second node provides a conflict response to a request for the data from the home node. The conflict response indicates that an ordering point for the data is migrating according to a second cache coherency protocol, which is different from the first cache coherency protocol.
摘要:
One disclosed embodiment is a multi-processor system comprising a processor having a processor pipeline that executes program instructions with data from a speculative fill that is provided in response to a source request. The multi-processor system can further comprise a non-retired store cache that retains non-retired store data based on program instructions to store data into a data cache associated with the processor. The non-retired store data can be written to the data cache if data of a speculative fill associated with the non-retired store data is determined to be coherent. Other apparatus and methodologies are disclosed.
摘要:
Multiprocessor systems and methods are disclosed. One embodiment may comprise a plurality of processor cores. A given processor core may be operative to generate a request for desired data in response to a cache miss at a local cache. A shared cache structure may provide at least one speculative data fill and a coherent data fill of the desired data to at least one of the plurality of processor cores in response to a request from the at least one processor core. A processor scoreboard arbitrates the requests for the desired data. A speculative data fill of the desired data is provided to the at least one processor core. The coherent data fill of the desired data may be provided to the at least one processor core in a determined order.
摘要:
A computer system including an instruction cache (I-cache) having a plurality of banks for storing a subset of data from memory is shown to include a prediction mechanism for predicting which bank of the I-cache contains the required data. A prediction value, including a sequential prediction hint and a branch prediction hint, is associated with each instruction stored in the I-cache. The prediction value may either be stored with the I-cache data, or in a separate memory included before the I-cache. If the predicted value is incorrect, the predicted hint is `trained` to provide a higher degree of accuracy for repetitive instruction stream operation. Processor performance is additionally improved by providing a branch hint that allows for smoother transition between changing instruction streams.
摘要:
A technique to enable resource allocation optimization within a computer system. In one embodiment, a gradient partition algorithm (GPA) module is used to continually measure performance and adjust allocation to shared resources among a plurality of data classes in order to achieve optimal performance.
摘要:
Methods for storing replacement data in a multi-way associative cache are disclosed. One method comprises logically dividing the cache's cache sets into segments of at least one cache way; searching a cache set in accordance with a segment search sequence for a segment currently comprising a way which has not yet been accessed during a current cycle of the segment search sequence; searching the current segment in accordance with a way search sequence for a way which has not yet been accessed during a current way search cycle; and storing the replacement data in a first way which has not yet been accessed during a current cycle of the way search sequence. A cache controller that performs such methods is also disclosed.
摘要:
Systems and methods are disclosed for updating owner predictor structures. In one embodiment, a multi-processor system includes an owner predictor control that provides an ownership update message corresponding to a block of data to at least one of a plurality of owner predictors in response to a change in an ownership state of the block of data. The update message comprises an address tag associated with the block of data and an identification associated with an owner node of the block of data.
摘要:
A system comprises a first node that provides a source broadcast request for data. The first node is operable to respond in a first manner to other source broadcast requests for the data while the source broadcast for the data is pending at the first node. The first node is operable to respond in a second manner to the other source broadcast requests for the data in response to receiving an ownership data response at the first node.
摘要:
A system comprises a first node including data having an associated D-state and a second node operative to provide a source broadcast requesting the data. The first node is operative in response to the source broadcast to provide the data to the second node and transition the state associated with the data at the first node from the D-state to an O-state without concurrently updating memory. An S-state is associated with the data at the second node.