Abstract: A compressed replay buffer in a first electronic unit of an electronic system holds commands in a table. As commands are transmitted from the first electronic unit to a second electronic unit, the command, along with associated data, command type, and the like are stored in a row in the table. No rows in the table contain “dead cycles” to indicate that no command was sent on a particular cycle on a bus over which the commands were transmitted. The second electronic unit may request that the first electronic unit replay some number of commands. In response, the first electronic unit uses commands in the compressed replay buffer, along with required timings stored on the first electronic unit, to replay the number of commands requested.

Abstract: In a method of initializing a computer memory that receives data from a plurality of redrive buffers, a predetermined data pattern of a selected set of data patterns is stored in selected redrive buffers of the plurality of redrive buffers. Each of the selected set of data patterns includes a first initialization data pattern and an error correcting code pattern that is a product of a logical function that operates on the first initialization data pattern and an address in the computer memory. The selected set of data patterns includes each possible value of error correcting code pattern. A redrive buffer of the plurality of redrive buffers that has stored therein an error correcting code pattern that corresponds to the selected address is selected when sending a first initialization data pattern to a selected address. The selected redrive buffer is instructed to write to the selected address the first initialization data pattern and the error correcting code pattern that corresponds to the selected address.

Abstract: Read commands on a mirrored memory computer system are scheduled by utilizing information about pending memory access requests. A conflict queue is configured to track a read/write queue associated with each of a plurality of memory ports on the mirrored memory system. The conflict queue determines a predicted latency on each memory port based on the contents of each of the read/write queues. A compare logic unit is coupled to the conflict queue, wherein the compare logic unit compares a predicted latency of a primary memory and a mirrored memory and schedules read commands to the memory port with the lowest predicted latency.

Abstract: A compressed replay buffer in a first electronic unit of an electronic system holds commands in a table. As commands are transmitted from the first electronic unit to a second electronic unit, the command, along with associated data, command type, and the like are stored in a row in the table. No rows in the table contain “dead cycles” to indicate that no command was sent on a particular cycle on a bus over which the commands were transmitted. The second electronic unit may request that the first electronic unit replay some number of commands. In response, the first electronic unit uses commands in the compressed replay buffer, along with required timings stored on the first electronic unit, to replay the number of commands requested.

Abstract: In a method of managing a cache directory in a memory system, an original system address is presented to the cache directory when corresponding associativity data is allocated to an associativity class in the cache directory. The original system address is normalized by removing address space corresponding to a memory hole, thereby generating a normalized address. The normalized address is stored in the cache directory. The normalized address is de-normalized, thereby generating a de-normalized address, when the associativity data is cast out of the cache directory to make room for new associativity data. The de-normalized address is sent to the memory system for coherency management.

Abstract: In a method of generating a cache directory to include a plurality of associativity classes, each associativity class includes an address tag including a plurality of address bits. Each address tag is configured to store a unique address to a specific location in an memory space. An amount of memory that is in an actually configured portion of the memory space is determined. A minimum number of bits necessary to address each memory location in the actually configured portion of the memory space is determined. Each address tag is configured in each associativity class to include the minimum number of bits necessary to address each memory location in the actually configured portion of the memory space. The cache directory is configured to include a maximum number of associativity classes per line in the cache directory.

Abstract: The present invention describes improving the scheduling of read commands on a mirrored memory computer system by utilizing information about pending memory access requests. A conflict queue is configured to track a read/write queue associated with each of a plurality of memory ports on the mirrored memory system. The conflict queue determines a predicted latency on each memory port based on the contents of each of the read/write queues. A compare logic unit is coupled to the conflict queue, wherein the compare logic unit compares a predicted latency of a primary memory and a mirrored memory and schedules read commands to the memory port with the lowest predicted latency.

Abstract: In a method of initializing a computer memory that receives data from a plurality of redrive buffers, a predetermined data pattern of a selected set of data patterns is stored in selected redrive buffers of the plurality of redrive buffers. Each of the selected set of data patterns includes a first initialization data pattern and an error correcting code pattern that is a product of a logical function that operates on the first initialization data pattern and an address in the computer memory. The selected set of data patterns includes each possible value of error correcting code pattern. A redrive buffer of the plurality of redrive buffers that has stored therein an error correcting code pattern that corresponds to the selected address is selected when sending an first initialization data pattern to a selected address. The selected redrive buffer is instructed to write to the selected address the first initialization data pattern and the error correcting code pattern that corresponds to the selected address.

Abstract: A method, system, and computer program product for tuning a set of chipset parameters to achieve optimal chipset performance under varying workload characteristics. A set of workload characteristics of a current workload type is determined. An instruction stream is generated using weighted parameters derived from the set of workload characteristics of the current workload type. A set of chipset parameters is generated and integrated within the instruction stream. The instruction stream is loaded to one or more processors and executed to collect and analyze performance data relating to the chipset's performance. The analysis includes comparing the set of performance data of a plurality of different instruction streams having the same set of workload characteristics. Each executed instruction stream is executed with at least one different combination of chipset parameters. A determination is made regarding which combination of chipset parameters provides the best performance data for the current workload.

Abstract: In a method of generating a cache directory to include a plurality of associativity classes, each associativity class includes an address tag including a plurality of address bits. Each address tag is configured to store a unique address to a specific location in an memory space. An amount of memory that is in an actually configured portion of the memory space is determined. A minimum number of bits necessary to address each memory location in the actually configured portion of the memory space is determined. Each address tag is configured in each associativity class to include the minimum number of bits necessary to address each memory location in the actually configured portion of the memory space. The cache directory is configured to include a maximum number of associativity classes per line in the cache directory.

Abstract: In a method of managing a cache directory in a memory system, an original system address is presented to the cache directory when corresponding associativity data is allocated to an associativity class in the cache directory. The original system address is normalized by removing address space corresponding to a memory hole, thereby generating a normalized address. The normalized address is stored in the cache directory. The normalized address is de-normalized, thereby generating a de-normalized address, when the associativity data is cast out of the cache directory to make room for new associativity data. The de-normalized address is sent to the memory system for coherency management.

Abstract: A method, system, and computer program product for tuning a set of chipset parameters to achieve optimal chipset performance under varying workload characteristics. A set of workload characteristics of a current workload type is determined. An instruction stream is generated using weighted parameters derived from the set of workload characteristics of the current workload type. A set of chipset parameters is generated and integrated within the instruction stream. The instruction stream is loaded to one or more processors and executed to collect and analyze performance data relating to the chipset's performance. The analysis includes comparing the set of performance data of a plurality of different instruction streams having the same set of workload characteristics. Each executed instruction stream is executed with at least one different combination of chipset parameters. A determination is made regarding which combination of chipset parameters provides the best performance data for the current workload.

Abstract: Methods and systems for re-ordering commands to access memory are disclosed. Embodiments may receive a first command to access a memory bank of the memory and determine a penalty associated with the first command based upon a conflict with an access to the memory bank. The penalty, in many embodiments, may be calculated so the penalty expires when the memory bank and a data bus associated with the memory bank are available to process the first command. Then, the first command is queued and dispatched to an available sequencer after the penalty expires. After the first command is serviced, unexpired penalties of subsequent commands may be updated to reflect a conflict with the first command. Further embodiments select a command to dispatch from the commands with expired penalties, based upon priorities associated with the commands such as the order in which the commands were received and the command types.