Abstract: A computer-implemented method includes, in a transactional memory environment comprising a plurality of processors, identifying one or more selected processors and identifying one or more coherence privilege state indicators. The one or more coherence privilege state indicators are associated with the one or more selected processors. A coherence privilege behavioral pattern is determined based on the one or more coherence privilege state indicators. A corresponding computer program product and computer system are also disclosed.

Abstract: A computer-implemented method includes, in a transactional memory environment comprising a plurality of processors, identifying one or more selected processors and identifying one or more coherence privilege state indicators. The one or more coherence privilege state indicators are associated with the one or more selected processors. A coherence privilege behavioral pattern is determined based on the one or more coherence privilege state indicators. A corresponding computer program product and computer system are also disclosed.

Abstract: A transactional memory system salvages a hardware lock elision (HLE) transaction. A processor of the transactional memory system, based on a detection of a pending point-of-failure in a code region during HLE transactional execution, stops HLE transactional execution prior to the pending point-of-failure in the code region. The processor, based on information about a lock elided, commits a speculative state of the stopped HLE transactional execution that is stored, at least in part, in a gathering store cache. The processor starts non-transactional execution at the point of failure in the code region.

Abstract: A computer system includes a processor, main memory, and controller. The processor includes a plurality of hardware threads configured to execute a plurality of software threads. The main memory includes a first register table configured to contain a current set of architected registers for the currently running software threads. The controller is configured to change a first number of the architected registers assigned to a given one of the software threads to a second number of architected registers when a result of monitoring current usage of the registers by the software threads indicates that the change will improve performance of the computer system. The processor includes a second register table configured to contain a subset of the architected registers and a mapping table for each software thread indicating whether the architected registers referenced by the corresponding software thread are located in the first register table or the second register table.

Abstract: Embodiments relate to implementing a coherence protocol. An aspect includes sending a request for data to a remote processor and receiving by a processor a response from the remote processor. The response has a transaction status of a remote transaction on the remote processor. The processor adds the transaction status of the remote transaction on the remote processor in a local transaction interference tracking table.

Abstract: A transactional memory system salvages a partially executed hardware transaction. A processor of the transactional memory system determines information about an about-to-fail handler for transactional execution of a code region of a hardware transaction. The processor then executes the about-to-fail handler using the information about the about-to-fail handler, the about-to-fail handler determining whether the hardware transaction is to be salvaged or to be aborted.

Abstract: A transactional memory system salvages a partially executed hardware transaction. A processor of the transactional memory system saves state information in a first code region of a first hardware transaction. The processor executes an about-to-fail handler, the about-to-fail handler using the saved state information to determine whether the first hardware transaction is to be salvaged or to be aborted. The processor executing the about-to-fail handler, based on the transaction being to be salvaged, uses the saved state information to determine what portion of the first hardware transaction to salvage.

Abstract: A computer-implemented method for cache memory management includes receiving a coherence request message from a requesting processor. The method can further include determining a request type responsive to detecting the transactional conflict. The request type is indicative of whether the coherence request is a prefetch request. The method further includes detecting, with a conflict detecting engine, a transactional conflict with the coherence request message. The method further includes sending, with the adaptive prefetch throttling engine, a negative acknowledgement to the requesting processor responsive to a determination that the coherence request is a prefetch request.

Abstract: A method for detecting a software-race condition in a program includes copying a state of a transaction of the program from a first core of a multi-core processor to at least one additional core of the multi-core processor, running the transaction, redundantly, on the first core and the at least one additional core given the state, outputting a result of the first core and the at least one additional core, and detecting a difference in the results between the first core and the at least one additional core, wherein the difference indicates the software-race condition.

Abstract: A scheme referred to as a “Region-based cache restoration prefetcher” (RECAP) is employed for cache preloading on a partition or a context switch. The RECAP exploits spatial locality to provide a bandwidth-efficient prefetcher to reduce the “cold” cache effect caused by multiprogrammed virtualization. The RECAP groups cache blocks into coarse-grain regions of memory, and predicts which regions contain useful blocks that should be prefetched the next time the current virtual machine executes. Based on these predictions, and using a simple compression technique that also exploits spatial locality, the RECAP provides a robust prefetcher that improves performance without excessive bandwidth overhead or slowdown.

Abstract: In a multi-processor transaction execution environment a transaction is executed a plurality of times. Based on the executions, a duration is predicted for executing the transaction. Based on the predicted duration, a threshold is determined. Pending aborts of the transaction due to memory conflicts are suppressed based on the transaction exceeding the determined threshold.

Abstract: Embodiments relate to implementing a coherence protocol. An aspect includes sending a request for data to a remote processor and receiving by a processor a response from the remote processor. The response has a transaction status of a remote transaction on the remote processor. The processor adds the transaction status of the remote transaction on the remote processor in a local transaction interference tracking table.

Abstract: A scheme referred to as a “Region-based cache restoration prefetcher” (RECAP) is employed for cache preloading on a partition or a context switch. The RECAP exploits spatial locality to provide a bandwidth-efficient prefetcher to reduce the “cold” cache effect caused by multiprogrammed virtualization. The RECAP groups cache blocks into coarse-grain regions of memory, and predicts which regions contain useful blocks that should be prefetched the next time the current virtual machine executes. Based on these predictions, and using a simple compression technique that also exploits spatial locality, the RECAP provides a robust prefetcher that improves performance without excessive bandwidth overhead or slowdown.

Abstract: Embodiments relate to address probing for a transaction. An aspect includes determining, before starting execution of a transaction, a plurality of addresses that will be used by the transaction during execution. Another aspect includes probing each address of the plurality of addresses to determine whether any of the plurality of addresses has an address conflict. Yet another aspect includes, based on determining that none of the plurality of addresses has an address conflict, starting execution of the transaction.

Abstract: A method, system, and computer program product are provided for prioritizing transactions. A processor in a computing environment initiates the execution of a transaction. The processor includes a transactional core, and the execution of the transaction is performed by the transactional core. The processor obtains concurrent with the execution of the transaction by the transactional core, an indication of a conflict between the transaction and at least one other transaction being executed by an additional core in the computing environment. The processor determines if the transactional core includes an indicator and based on determining that the transactional core includes an indicator, the processor ignores the conflict and utilizing the transactional core to complete executing the transaction.

Abstract: Embodiments relate to thread-based cache content savings for task switching in a computer processor. An aspect includes determining a cache entry in a cache of the computer processor that is owned by the first thread, wherein the determination is made based on a hardware thread identifier (ID) of the first thread matching a hardware thread ID in the cache entry. Another aspect includes determining whether the determined cache entry is eligible for prefetching. Yet another aspect includes, based on determining that the determined cache entry is eligible for prefetching, setting a marker in the cache entry to active.

Abstract: Embodiments relate to address probing for a transaction. An aspect includes determining, before starting execution of a transaction, a plurality of addresses that will be used by the transaction during execution. Another aspect includes probing each address of the plurality of addresses to determine whether any of the plurality of addresses has an address conflict. Yet another aspect includes, based on determining that none of the plurality of addresses has an address conflict, starting execution of the transaction.

Abstract: There is provided an apparatus, a method and computer program product for managing one or more components of an electronic machine. A user connects one or more components to an electronic machine in parallel. The electronic machine determines whether the components are failed. A latch device, attached to each component, automatically locks one or more of the components to the electronic machine if the one or more of the components are not failed. The electromechanical latch automatically releases the one or more of the components from the electronic machine if the one or more of the components are failed.

Abstract: A transactional memory system determines whether to pass control of a transaction to an about-to-run-out-of-resource handler. A processor of the transactional memory system determines information about an about-to-run-out-of-resource handler for transaction execution of a code region of a hardware transaction. The processor dynamically monitors an amount of available resource for the currently running code region of the hardware transaction. The processor detects that the amount of available resource for transactional execution of the hardware transaction is below a predetermined threshold level. The processor, based on the detecting, saves speculative state information of the hardware transaction, and executes the about-to-run-out-of-resource handler, the about-to-run-out-of-resource handler determining whether the hardware transaction is to be aborted or salvaged.

Abstract: Cache lines in a multi-processor computing environment are configurable with a coherency mode. Cache lines in full-line coherency mode are operated or managed with full-line granularity. Cache lines in sub-line coherency mode are operated or managed as sub-cache line portions of a full cache line. Each cache is associated with a directory having a number of directory entries and with a side table having a smaller number of entries. The directory entry for a cache line associates the cache line with a tag and a set of full-line descriptive bits. Creating a side table entry for the cache line places the cache line in sub-line coherency mode. The side table entry associates each of the sub-cache line portions of the cache line with a set of sub-line descriptive bits. Removing the side table entry may return the cache line to full-line coherency mode.