International Business Machines Corporation

Kenneth Douglas Klapproth

Michael Andrew Blake

Robert J Sonnelitter, Iii

Timothy Carl Bronson

Hieu Trong Huynh

Vesselina K Papazova

Guy G Tracy

Deanna Postles Dunn Berger

Ashraf ElSharif

Michael F Fee

Craig Raymond Walters

David Mui

Tim Bronson

Pak-kin Mak

Ekaterina M Ambroladze

Garrett M Drapala

Manuel Joseph Alvarez, Ii

Jason D Kohl

Jason Raymond Baumgartner

Sanjay Raghunath Deshpande

Mark R Hodges

Ram Sai Manoj Bamdhamravuri

Arun Kwangil Iyengar

Matthias Klein

Steven Leonard Roberts

Arthur J O'Neill

Mark Andrew Brittain

Deanna P Berger

Charlie Chornglii Hwang

Chad G Wilson

Deanna P D Berger

Joseph J Palumbo

Avery Francois

Flemming Andersen

Kevin Lopes

Chunggeon Rhee

Arthur o'Neill

Anna Mozeshtam

Vu T Le

Embodiments include processing commands on multiprocessor chip having a plurality of nodes that are interconnected via a clockwise ring network and a counterclockwise ring network. Aspects include receiving, by a first ring station associated with a first node of the plurality of nodes, the command for execution and transmitting, by the first ring station via one or more of the clockwise ring network and the counterclockwise ring network, the command for execution. Aspects also include receiving, by a second ring station associated with a second node of the plurality of nodes, the command for execution, wherein the second ring station is connected to a third ring station associated with a third node of the plurality of nodes via a first cross bar of the one or more cross bars and transmitting, by the second ring station to the third ring station via the first cross bar, the command for execution.

Bidirectional ring-based interconnection networks having a cross bar for multiprocessors

Methods, systems and computer program products for providing access to a spare memory array element ('MAE') are provided. Aspects include storing a row number a column number associated with a defective MAE of a plurality of MAEs. The plurality of MAEs are logically arranged in a plurality of rows and a plurality of columns. Aspects also include receiving a command to access a cache line. The cache line corresponds to a selected row of MAEs of the plurality of MAEs. Responsive to determining that the selected row matches the row number that is associated with the defective MAE, aspects include activating one or more column shifters to prevent access to the defective MAE and provide access to a spare MAE when accessing the cache line. The activation of the one of more column shifters is based on the column number that is associated with the defective MAE.

Memory array element sparing

According to one or more embodiments, a method for adding parity protection for any uncovered latches of a circuit design is provided. The method includes determining latches that are not covered by current parity protection of the circuit design to output a list of the uncovered latches. The method includes executing a clustering operation that iteratively generates latch groupings according to physical design information and clock gating domains, and that outputs an updated design incorporating the latch groupings. Note that each latch grouping generates a corresponding parity bit to provide the parity protection to minimize adverse impacts on timing, routing, and power consumption of the circuit design. The method also includes adding the updated design with the parity protection to the circuit design to generate a final hardware design.

Placement-driven generation of error detecting structures in integrated circuits

Embodiments of the present invention are directed to a computer-implemented method for cache eviction. The method includes detecting a first data in a shared cache and a first cache in response to a request by a first processor. The first data is determined to have a mid-level cache eviction priority. A request is detected from a second processor for a same first data as requested by the first processor. However, in this instance, the second processor has indicated that the same first data has a low-level cache eviction priority. The first data is duplicated and loaded to a second cache, however, the data has a low-level cache eviction priority at the second cache.

Multilevel cache eviction management

Methods, systems and computer program products for measuring hardware performance are provided. Aspects include receiving an indication of a start to a hardware operation. A number of clock cycles are counted from the start of a hardware operation to the completion of the hardware operation. A first region comprising a first set of bit location is defined. A second and third region is defined each including a set of bit locations. Based on the first set of bit locations being equal to zero, a granularity flag is set to zero in the sample buffer and the second and third set of bit locations are written to the sample buffer. And based on the first set of bit locations being greater than zero, the granularity flag in the sample buffer is set to one and the first and second set of bit locations are written to the sample buffer.

Accuracy sensitive performance counters

Processing simultaneous data requests regardless of active request in the same addressable index of a cache. In response to the cache miss in the given congruence, if the number of other compartments in the given congruence class that have an active operation is less than a predetermined threshold, setting a Do Not Cast Out (DNCO) pending indication for each of the compartments that have an active operation in order to block access to each of the other compartments that have active operations and, if the number of other compartments in the given congruence class that have an active operation is not less than a predetermined threshold, blocking another cache miss from occurring in the compartments of the given congruence class by setting a congruence class block pending indication for the given congruence class in order to block access to each of the other compartments of the given congruence class.

Coherent cache with simultaneous data requests in same addressable index

Provided are systems, methods, and media for simultaneous, non-atomic request processing of snooped operations of a broadcast scope within a SMP system. An example method includes detecting, by a first controller, based on a set of coherency resolution conditions, whether there are coherency resolution problems between two snooped operations. The method includes in response to detecting, by the first controller, that coherency resolution problems will not result, transmitting, from the first controller to a second controller, an indication signal indicating that coherency resolution problems will not result from the operation. The set of coherency resolution conditions includes: (a) detecting that a second operation of the two snooped operations operation is of a predetermined type, (b) detecting at time of snooping of the second operation that a directory state does not allow for exclusive data, and (c) detecting that the first controller has started committing to an update.

Simultaneous, non-atomic request processing within an SMP environment broadcast scope for multiply-requested data elements using real-time parallelization

Embodiments of the present invention are directed to a computer-implemented method for ownership tracking updates across multiple simultaneous operations. A non-limiting example of the computer-implemented method includes receiving, by a cache directory control circuit, a message to update a cache directory entry. The method further includes, in response, updating, by the cache directory control circuit, the cache directory entry, and generating a reverse compare signal including an updated ownership vector of a memory line corresponding to the cache directory entry. The method further includes sending the reverse compare signal to a cache controller associated with the cache directory entry.

Ownership tracking updates across multiple simultaneous operations

An aspect includes interlocking operations in an address-sliced cache system. A computer-implemented method includes determining whether a dynamic memory relocation operation is in process in the address-sliced cache system. Based on determining that the dynamic memory relocation operation is in process, a key operation is serialized to maintain a sequenced order of completion of the key operation across a plurality of slices and pipes in the address-sliced cache system. Based on determining that the dynamic memory relocation operation is not in process, a plurality of key operation requests is allowed to launch across two or more of the slices and pipes in parallel in the address-sliced cache system while ensuring that only one instance of the key operations is in process across all of the slices and pipes at a same time.

Operation interlocking in an address-sliced cache system

In one embodiment, a computer-implemented method includes instructing two or more processors that are operating in a normal state of a symmetric multiprocessing (SMP) network to transition from the normal state to a slow state. The two or more processors reduce their frequencies to respective target frequencies in a transitional state when transitioning from the normal state to the slow state. It is determined that the two or more processors have achieved their respective target frequencies for the slow state. The slow state is entered, responsive to this determination. Responsive to entering the slow state, a first processor of the two or more processors is instructed to send empty packets across an interconnect to compensate for a first greatest potential rate differential between the first processor and a remainder of the two or more processors during the slow state.

Dynamic synchronous to asynchronous frequency transitions in high-performance symmetric multiprocessing

Embodiments relate to storing data to a system memory. An aspect includes accessing successive entries of a cache directory having a plurality of directory entries by a stepper engine, where access to the cache directory is given a lower priority than other cache operations. It is determined that a specific directory entry in the cache directory has a change line state that indicates it is modified. A store operation is performed to send a copy of the specific corresponding cache entry to the system memory as part of a cache management function. The specific directory entry is updated to indicate that the change line state is unmodified.

Storing data in a system memory for a subsequent cache flush

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Austin, TX, United States of America

Kenneth Douglas Klapproth