Abstract: An aspect includes a system architecture that includes a processing unit, an accelerator, a main source buffer, a main target buffer, and a memory block. The main source buffer stores a first part of a source symbol received from an external source. The main target buffer stores an output symbol received from the accelerator. The memory block includes an overflow source buffer that stores the first part of the source symbol received from the main source buffer. The accelerator fetches the first part of the source symbol stored in the overflow source buffer and a second part of the source symbol stored in the main source buffer, and converts the first and second parts of the source symbol together into the output symbol. The second part of the source symbol includes a part of the source symbol not included in the first part of the source symbol.

Abstract: A conditional instruction end facility is provided that allows completion of an instruction to be delayed. In executing the machine instruction, an operand is obtained, and a determination is made as to whether the operand has a predetermined relationship with respect to a value. Based on determining that the operand does not have the predetermined relationship with respect to the value, the obtaining and the determining are repeated. Based on determining that the operand has the predetermined relationship with respect to the value, execution of the instruction is completed.

Abstract: An address translation facility is provided for multiple virtualization levels, where a guest virtual address may be translated to a guest non-virtual address, the guest non-virtual address corresponding without translation to a host virtual address, and the host virtual address may be translated to a host non-virtual address, where translation within a virtualization level may be specified as a sequence of accesses to address translation tables. The address translation facility may include a first translation engine and a second translation engine, where the first and second translation engines each have capacity to perform address translation within a single virtualization level of the multiple virtualization levels.

Abstract: Controlling a rate of prefetching based on bus bandwidth. A determination is made as to whether a rate of prefetching data from memory into a cache is to be changed. This determination is based on bus utilization, and includes identifying a most utilized bus of a plurality of buses used for the prefetch of data, and monitoring utilization of the most utilized bus. The determination whether the rate of prefetching is to be changed is based on the monitoring. Based on determining that the rate is to be changed, the rate of prefetching is changed.

Abstract: Speculative data return in parallel with an exclusive invalidate request. A requesting processor requests data from a shared cache. The data is owned by another processor. Based on the request, an invalidate request is sent to the other processor requesting the other processor to release ownership of the data. Concurrent to the invalidate request being sent to the other processor, the data is speculatively provided to the requesting processor.

Abstract: Controlling a rate of prefetching based on bus bandwidth. A determination is made as to whether a rate of prefetching data from memory into a cache is to be changed. This determination is based on bus utilization. Based on determining that the rate is to be changed, the rate of prefetching is changed.

Abstract: A Spin Loop Delay instruction. The instruction has a field associated therewith that indicates one or more conditions to be checked. Dispatching of the instruction is initially delayed. The instruction is subsequently dispatched based on a timeout, provided the instruction has not been previously dispatched based on meeting at least one condition of the one or more conditions to be checked.

Abstract: Executing a Next Instruction Access Intent instruction by a computer. The processor obtains an access intent instruction indicating an access intent. The access intent is associated with an operand of a next sequential instruction. The access intent indicates usage of the operand by one or more instructions subsequent to the next sequential instruction. The computer executes the access intent instruction. The computer obtains the next sequential instruction. The computer executes the next sequential instruction, whose execution comprises, based on the access intent, adjusting one or more cache behaviors for the operand of the next sequential instruction.

Abstract: A method and a system detects a cache line as a potential or confirmed hot cache line based on receiving an intervention of a processor associated with a fetch of the cache line. The method and system include suppressing an action of operations associated with the hot cache line. A related method and system detect an intervention and, in response, communicates an intervention notification to another processor. An alternative method and system detect a hot data object associated with an intervention event of an application. The method and system can suppress actions of operations associated with the hot data object. An alternative method and system can detect and communicate an intervention associated with a data object.

Abstract: A method of optimized congruence class matching for concurrent memory translation requests to avoid memory access conflicts with respect to a virtual memory managed by a processor is provided. The method includes initiating a first table walk by a first memory access of the concurrent memory translation requests and pending a subsequent table walk initiated by a subsequent memory access of the concurrent memory translation requests. Then, the method determines whether the subsequent table walk will cause a memory access conflict with the first table walk based on the optimized congruence class matching. The subsequent memory access is rejected when the subsequent table walk will cause the memory access conflict with the first table walk.

Abstract: Storage accesses for merge operations are minimized. A plurality of records of a plurality of input lists are merged. The merging includes determining that an input list of the plurality of input lists has become empty, and checking, based on determining that the input list has become empty, a control specific for the input list. The control is used to determine how to proceed, such as whether to end merging or continue merging.

Abstract: Migration of partially completed instructions. A determination is made that processing of an operation of an instruction executing on a processor has been interrupted prior to completion. The instruction is re-executed on a selected processor to resume forward processing of the instruction. The re-executing includes determining whether model-dependent metadata is to be used by the selected processor in re-executing the instruction. Based on determining the model-dependent metadata is to be used, the model-dependent metadata is used in re-executing the instruction. Based on determining the model-dependent metadata is not to be used, proceeding with re-executing the instruction without using the model-dependent metadata.

Abstract: A Sort Lists instruction is provided to perform a sort and/or a merge operation. The instruction is an architected machine instruction of an instruction set architecture and is executed by a general-purpose processor of the computing environment. The executing includes sorting a plurality of input lists to obtain one or more sorted output lists, which are output.

Abstract: Saving and restoring machine state between multiple executions of an instruction. A determination is made that processing of an operation of an instruction executing on a processor has been interrupted prior to completion. Based on determining that the processing of the operation has been interrupted, current metadata of the processor is extracted. The metadata is stored in a location associated with the instruction and used to re-execute the instruction to resume forward processing of the instruction from where it was interrupted.

Abstract: Controlling a rate of prefetching based on bus bandwidth. A determination is made as to whether a rate of prefetching data from memory into a cache is to be changed. This determination is based on bus utilization. Based on determining that the rate is to be changed, the rate of prefetching is changed.

Abstract: An address translation facility is provided for multiple virtualization levels, where a guest virtual address may be translated to a guest non-virtual address, the guest non-virtual address corresponding without translation to a host virtual address, and the host virtual address may be translated to a host non-virtual address, where translation within a virtualization level may be specified as a sequence of accesses to address translation tables. The address translation facility may include a first translation engine and a second translation engine, where the first and second translation engines each have capacity to perform address translation within a single virtualization level of the multiple virtualization levels.

Abstract: A computer processor includes a memory unit that stores key values to be loaded into a partial tournament sort, and a processor cache that obtains tree data from the memory unit indicating the key values. A hardware merge sort accelerator generates a tournament tree based on the key values, and performs a partial tournament sort to store a first portion of tournament results in the processor cache while excluding a second portion of the tournament results from the processor cache.

Abstract: An address translation facility is provided for multiple virtualization levels, where a guest virtual address may be translated to a guest non-virtual address, the guest non-virtual address corresponding without translation to a host virtual address, and the host virtual address may be translated to a host non-virtual address, where translation within a virtualization level may be specified as a sequence of accesses to address translation tables. The address translation facility may include a first translation engine and a second translation engine, where the first and second translation engines each have capacity to perform address translation within a single virtualization level of the multiple virtualization levels.

Abstract: A computing environment facility is provided to extend a hold of a cache line in private (or local) cache exclusively after processing a storage operand request. The facility includes determining whether a storage operand request to a storage location shared by multiple processing units of the computing environment is designated hold. In addition, a determination is made whether a state of the corresponding cache line in private cache used for processing the storage operand request is owned exclusively. Based on determining that the storage operand request is designated hold, and that the state of the corresponding cache line in private cache used for processing the storage operand request is owned exclusively, continuing to hold the corresponding cache line in the private cache exclusively after completing processing of the storage operand request. The continuing to hold may include initiating a counter to facilitate the continuing hold for a desired, set interval.

Abstract: A computer implemented method to operate different processor cache levels of a cache hierarchy for a processor with pipelined execution is suggested. The cache hierarchy comprises at least a lower hierarchy level entity and a higher hierarchy level entity. The method comprises: sending a fetch request to the cache hierarchy; detecting a miss event from a lower hierarchy level entity; sending a fetch request to a higher hierarchy level entity; and scheduling at least one write pass.