Abstract: A job scheduler can select a processor core operating frequency for a node in a cluster to perform a job based on energy usage and performance data. After a job request is received, an energy aware job scheduler accesses data that specifies energy usage and job performance metrics that correspond to the requested job and a plurality of processor core operating frequencies. A first of the plurality of processor core operating frequencies is selected that satisfies an energy usage criterion for performing the job based, at least in part, on the data that specifies energy usage and job performance metrics that correspond to the job. The job is assigned to be performed by a node in the cluster at the selected first of the plurality of processor core operating frequencies.

Abstract: Candidate solutions to an optimization problem comprise a set of potential values that can be applied to variables in a problem description. Candidate solutions can be large because of the complexity of optimization problems and large number of variables. The populations of candidate solutions may also be large to ensure diversity and effectiveness in computing a solution. When the populations and the candidate solutions are large for an optimization problem, computing a solution to the optimization problem consumes a large amount of memory. In some instances, several generations of candidate solutions are stored in memory. Compression of the candidate solutions can minimize the memory space consumed to compute a solution to an optimization problem.

Abstract: A processor having multiple cores coordinates functions performed on the cores to automatically, dynamically and repeatedly reconfigure the cores for optimal performance based on characteristics of currently executing software. A core running a thread detects a multi-core characteristic of the thread and assigns one or more other cores to the thread to dynamically combine the cores into what functionally amounts to a common core for more efficient execution of the thread.

Abstract: A method and apparatus for speculatively executing a single threaded program within a multi-core processor which includes identifying an idle core within the multi-core processor, performing a look ahead operation on the single thread instructions to identify speculative instructions within the single thread instructions, and allocating the idle core to execute the speculative instructions.

Abstract: Some embodiments of the inventive subject matter are directed to determining that a memory access request results in a cache miss and determining an amount of cache resources used to service cache misses within a past period in response to determining that the memory access request results in the cache miss. Some embodiments are further directed to determining that servicing the memory access request would increase the amount of cache resources used to service cache misses within the past period to exceed a threshold. In some embodiments, the threshold corresponds to reservation of a given amount of cache resources for potential cache hits. Some embodiments are further directed to rejecting the memory access request in response to the determining that servicing the memory access request would increase the amount of cache resources used to service cache misses within the past period to exceed the threshold.

Abstract: Some embodiments of the inventive subject matter are directed to a cache comprising a tracking unit and cache state machines. In some embodiments, the tracking unit is configured to track an amount of cache resources used to service cache misses within a past period. In some embodiments, each of the cache state machines is configured to, determine whether a memory access request results in a cache miss or cache hit, and in response to a cache miss for a memory access request, query the tracking unit for the amount of cache resources used to service cache misses within the past period. In some embodiments, the each of the cache state machines is configured to service the memory access request based, at least in part, on the amount of cache resources used to service the cache misses within the past period according to the tracking unit.

Abstract: A method utilizes information provided by performance monitoring hardware to dynamically adjust the number of levels of speculative branch predictions allowed (typically 3 or 4 per thread). for a processor core. The information includes cycles-per-instruction (CPI) for the processor core and number of memory accesses per unit time. If the CPI is below a CPI threshold; and the number of memory accesses (NMA) per unit time is above a prescribe threshold, the number of levels of speculative branch predictions is reduced per thread for the processor core. Likewise, the number of levels of speculative branch predictions could be increased, from a low level to maximum allowed, if the CPI threshold is exceeded or the number of memory accesses per unit time is below the prescribed threshold.

Abstract: A storage subsystem combining solid state drive (SSD) and hard disk drive (HDD) technologies provides low access latency and low complexity. Separate free lists are maintained for the SSD and the HDD and blocks of file system data are stored uniquely on either the SSD or the HDD. When a read access is made to the subsystem, if the data is present on the SSD, the data is returned, but if the block is present on the HDD, it is migrated to the SSD and the block on the HDD is returned to the HDD free list. On a write access, if the block is present in the either the SSD or HDD, the block is overwritten, but if the block is not present in the subsystem, the block is written to the HDD.

Abstract: According to one aspect of the present disclosure, a system and technique for variable cache line size management is disclosed. The system includes a processor and a cache hierarchy, where the cache hierarchy includes a sectored upper level cache and an unsectored lower level cache, and wherein the upper level cache includes a plurality of sub-sectors, each sub-sector having a cache line size corresponding to a cache line size of the lower level cache. The system also includes logic executable to, responsive to determining that a cache line from the upper level cache is to be evicted to the lower level cache: identify referenced sub-sectors of the cache line to be evicted; invalidate unreferenced sub-sectors of the cache line to be evicted; and store the referenced sub-sectors in the lower level cache.

Abstract: According to one aspect of the present disclosure, a method and technique for variable cache line size management is disclosed. The method includes: determining whether an eviction of a cache line from an upper level sectored cache to an unsectored lower level cache is to be performed, wherein the upper level cache includes a plurality of sub-sectors, each sub-sector having a cache line size corresponding to a cache line size of the lower level cache; responsive to determining that an eviction is to be performed, identifying referenced sub-sectors of the cache line to be evicted; invalidating unreferenced sub-sectors of the cache line to be evicted; and storing the referenced sub-sectors in the lower level cache.

Abstract: Secure communication of data between devices includes encrypting unencrypted data at a first device by reordering unencrypted bits provided in parallel on a device bus, including data and control bits, from an unencrypted order to form encrypted data including a plurality of encrypted bits in parallel in an encrypted order defined by a key. The encrypted data may be transmitted to another device where the encrypted data is decrypted by using the key to order the encrypted bits to restore the unencrypted order thereby to reform the unencrypted data.

Abstract: A processor has multiple cores with each core having an associated function to support processor operations. The functions performed by the cores are selectively altered to improve processor operations by balancing the resources applied for each function. For example, each core comprises a field programmable array that is selectively and dynamically programmed to perform a function, such as a floating point function or a fixed point function, based on the number of operations that use each function. As another example, a processor is built with a greater number of cores than can be simultaneously powered, each core associated with a function, so that cores having functions with lower utilization are selectively powered down.

Abstract: A method and processor chip design for enabling a processor core to continue sending store operations speculatively to the store queue after the core receives indication that the store queue is full. The processor core is configured with speculative store logic that enables the processor core to continue issuing store operations while the store queue full signal is asserted. A copy of the speculatively issued store operation is placed within a speculative store buffer. The core waits for a signal from the store queue indicating the store operation was accepted into the store queue. When the speculatively-issued store operation is accepted within the store queue, the copy is discarded from the buffer. However, when the store operation is rejected, the speculative store logic re-issues the store operation ahead of normal store operations.

Abstract: A processor blade determines whether a selected processing task is to be off-loaded to a storage blade for processing. The selected processing task is off-loaded to the storage blade via a planar bus communication path, in response to determining that the selected processing task is to be off-loaded to the storage blade. The off-loaded selected processing task is processed in the storage blade. The storage blade communicates the results of the processing of the off-loaded selected processing task to the processor blade.

Abstract: A processor has multiple cores with each core having an associated function to support processor operations. The functions performed by the cores are selectively altered to improve processor operations by balancing the resources applied for each function. For example, each core comprises a field programmable array that is selectively and dynamically programmed to perform a function, such as a floating point function or a fixed point function, based on the number of operations that use each function. As another example, a processor is built with a greater number of cores than can be simultaneously powered, each core associated with a function, so that cores having functions with lower utilization are selectively powered down.

Abstract: A method for optimizing execution of a single threaded program on a multi-core processor. The method includes dividing the single threaded program into a plurality of discretely executable components while compiling the single threaded program; identifying at least some of the plurality of discretely executable components for execution by an idle core within the multi-core processor; and enabling execution of the at least one of the plurality of discretely executable components on the idle core.

Abstract: Provided are a computer program product, system, and method for determining server write activity levels to use to adjust write cache size. Information on server write activity to the cache is gathered. The gathered information on write activity is processed to determine a server write activity level comprising one of multiple write activity levels indicating a level of write activity. The determined server write activity level is transmitted to a storage server having a write cache, wherein the storage server uses the determined server write activity level to determine whether to adjust a size of the storage server write cache.

Abstract: A method for preserving memory affinity in a computer system is disclosed. The method reduces and sometimes eliminates memory affinity loss due to process migration by restoring the proper memory affinity through dynamic page migration. The memory affinity access patterns of individual pages are tracked continuously. If a particular page is found almost always to be accessed from a particular remote access affinity domain for a certain number of times, and without any intervening requests from other access affinity domain, the page will migrate to that particular remote affinity domain so that the subsequent memory access becomes local memory access. As a result, the proper pages are migrated to increase memory affinity.

Abstract: A job scheduler can select a processor core operating frequency for a node in a cluster to perform a job based on energy usage and performance data. After a job request is received, an energy aware job scheduler accesses data that specifies energy usage and job performance metrics that correspond to the requested job and a plurality of processor core operating frequencies. A first of the plurality of processor core operating frequencies is selected that satisfies an energy usage criterion for performing the job based, at least in part, on the data that specifies energy usage and job performance metrics that correspond to the job. The job is assigned to be performed by a node in the cluster at the selected first of the plurality of processor core operating frequencies.

Abstract: A cache within a computer system receives a partial write request and identifies a cache hit of a cache line. The cache line corresponds to the partial write request and includes existing data. In turn, the cache receives partial write data and merges the partial write data with the existing data into the cache line. In one embodiment, the existing data is “modified” or “dirty.” In another embodiment, the existing data is “shared.” In this embodiment, the cache changes the state of the cache line to indicate the storing of the partial write data into the cache line.