摘要:
According to a method of data processing, a memory controller receives a prefetch load request from a processor core of a data processing system. The prefetch load request specifies a requested line of data. In response to receipt of the prefetch load request, the memory controller determines by reference to a stream of demand requests how much data is to be supplied to the processor core in response to the prefetch load request. In response to the memory controller determining to provide less than all of the requested line of data, the memory controller provides less than all of the requested line of data to the processor core.
摘要:
A technique for performing data prefetching using multi-level indirect data prefetching includes determining a first memory address of a pointer associated with a data prefetch instruction. Content that is included in a first data block (e.g., a first cache line of a memory) at the first memory address is then fetched. A second memory address is then determined based on the content at the first memory address. Content that is included in a second data block (e.g., a second cache line) at the second memory address is then fetched (e.g., from the memory or another memory). A third memory address is then determined based on the content at the second memory address. Finally, a third data block (e.g., a third cache line) that includes another pointer or data at the third memory address is fetched (e.g., from the memory or the another memory).
摘要:
A technique for data prefetching using indirect addressing includes monitoring data pointer values, associated with an array, in an access stream to a memory. The technique determines whether a pattern exists in the data pointer values. A prefetch table is then populated with respective entries that correspond to respective array address/data pointer pairs based on a predicted pattern in the data pointer values. Respective data blocks (e.g., respective cache lines) are then prefetched (e.g., from the memory or another memory) based on the respective entries in the prefetch table.
摘要:
A technique for performing data prefetching using indirect addressing includes determining a first memory address of a pointer associated with a data prefetch instruction. Content, that is included in a first data block (e.g., a first cache line) of a memory, at the first memory address is then fetched. An offset is then added to the content of the memory at the first memory address to provide a first offset memory address. A second memory address is then determined based on the first offset memory address. A second data block (e.g., a second cache line) that includes data at the second memory address is then fetched (e.g., from the memory or another memory). A data prefetch instruction may be indicated by a unique operational code (opcode), a unique extended opcode, or a field (including one or more bits) in an instruction.
摘要:
A method of data processing in a processor includes maintaining a usage history indicating demand usage of prefetched data retrieved into cache memory. An amount of data to prefetch by a data prefetch request is selected based upon the usage history. The data prefetch request is transmitted to a memory hierarchy to prefetch the selected amount of data into cache memory.
摘要:
A processor includes a first address translation engine, a second address translation engine, and a prefetch engine. The first address translation engine is configured to determine a first memory address of a pointer associated with a data prefetch instruction. The prefetch engine is coupled to the first translation engine and is configured to fetch content, included in a first data block (e.g., a first cache line) of a memory, at the first memory address. The second address translation engine is coupled to the prefetch engine and is configured to determine a second memory address based on the content of the memory at the first memory address. The prefetch engine is also configured to fetch (e.g., from the memory or another memory) a second data block (e.g., a second cache line) that includes data at the second memory address.
摘要:
According to method of data processing in a multiprocessor data processing system, in response to a processor touch request targeting a target granule of a cache line of data containing multiple granules, a processing unit originates on an interconnect of the multiprocessor data processing system a partial touch request that requests a copy of only the target granule for subsequent query access. In response to a combined response to the partial touch request indicating success, the combined response representing a system-wide response to the partial touch request, the processing unit receives the target granule of the target cache line and updates a coherency state of the target granule while retaining a coherency state of at least one other granule of the cache line.
摘要:
According to a method of data processing, a memory controller receives a prefetch load request from a processor core of a data processing system. The prefetch load request specifies a requested line of data. In response to receipt of the prefetch load request, the memory controller determines by reference to a stream of demand requests how much data is to be supplied to the processor core in response to the prefetch load request. In response to the memory controller determining to provide less than all of the requested line of data, the memory controller provides less than all of the requested line of data to the processor core.
摘要:
A technique for performing indirect data prefetching includes determining a first memory address of a pointer associated with a data prefetch instruction. Content of a memory at the first memory address is then fetched. A second memory address is determined from the content of the memory at the first memory address. Finally, a data block (e.g., a cache line) including data at the second memory address is fetched (e.g., from the memory or another memory).
摘要:
A technique for performing data prefetching using multi-level indirect data prefetching includes determining a first memory address of a pointer associated with a data prefetch instruction. Content that is included in a first data block (e.g., a first cache line of a memory) at the first memory address is then fetched. A second memory address is then determined based on the content at the first memory address. Content that is included in a second data block (e.g., a second cache line) at the second memory address is then fetched (e.g., from the memory or another memory). A third memory address is then determined based on the content at the second memory address. Finally, a third data block (e.g., a third cache line) that includes another pointer or data at the third memory address is fetched (e.g., from the memory or the another memory).