Abstract: Channel marking is provided in a memory system that includes a first memory channel, a second memory channel, and error correction code (ECC) logic. The memory system is configured to perform a method that includes receiving a request to apply a first channel mark to the first memory channel and determining a priority level of the first channel mark. A request is received to apply a second channel mark to the second memory channel, and a priority level of the second mark is determined. It is determined that the priority level of the first channel mark is higher than the priority level of the second channel mark. The first channel mark is supplied to the ECC logic while blocking the second channel mark from the ECC logic.

Abstract: Providing heterogeneous recovery in a redundant memory system that includes a memory controller, a plurality of memory channels in communication with the memory controller, an error detection code mechanism configured for detecting a failing memory channel, and an error recovery mechanism. The error recovery mechanism is configured for receiving notification of the failing memory channel, for performing a recovery operation on the failing memory channel while other memory channels are performing normal system operations, for bringing the recovered channel back into operational mode with the other memory channels for store operations, for continuing to mark the recovered channel to guard against stale data, for removing any stale data after the recovery operation is complete, and for removing the mark on the recovered channel to allow the normal system operations with all of the memory channels, the removing based on the removing any stale data being complete.

Abstract: A computer implemented method for providing homogeneous recovery in a redundant memory system. The method includes receiving a notification that a memory channel has failed, where the memory channel is one of a plurality of memory channels in a memory system. New operations are blocked from starting on the memory channels in response to the notification, and any pending operations on the memory channels are completed in response to the notification. A recovery operation is performed on the memory channels in response to the completing. The new operations are started on at least a first subset of the memory channels in response to the recovery operation completing. The memory system is configured to operate with the first subset of the memory channels.

Abstract: A method includes modifying, at a bit error injection circuit, a multiplier value by a first value according to an occurrence of a first event. The method also includes, in response to a determination that the modified multiplier value matches a first threshold, modifying, at the bit error injection circuit, the offset value according to an occurrence of a second event. The method further includes, in response to a determination that the modified offset value matches a second threshold, asserting, at the bit error injection circuit, an error injection signal. The method further includes asserting a first error pattern to be transmitted via a bus lane based on the error injection signal.

Abstract: Marking memory chips as faulty when a fault is detected in data from the memory chip. Upon detecting that a plurality of memory chips are faulty, determining which of a plurality of memory channels contains the faulty memory chips. Marking one of a plurality of memory channels as failing in response to determining that the number of failing memory chips has exceeded a threshold.

Abstract: Dynamic graduated memory device protection in redundant array of independent memory (RAIM) systems that include a plurality of memory devices is provided. A first severity level of a first failing memory device in the plurality of memory devices is determined. The first failing memory device is associated with an identifier used to communicate a location of the first failing memory device to an error correction code (ECC). A second severity level of a second failing memory device in the plurality of memory devices is determined. It is determined that the second severity level is higher than the first severity level. The identifier from the first failing memory device is removed based on determining that the second severity level is higher than the first severity level. The identifier is applied to the second failing memory device based on determining that the second severity level is higher than the first severity level.

Abstract: Channel marking is provided in a memory system that includes a memory channel with a plurality of memory devices. The memory devices are arranged into a first group of memory devices and a second group of memory devices. The memory system is configured to perform a method that includes determining that more than a threshold number of memory devices in the first group are failing. An error correction code (ECC) is configured to compensate for errors associated with memory devices in the first group on the memory channel and to perform error correction on errors associated with memory devices in the second group on the memory channel.

Abstract: Providing heterogeneous recovery in a redundant memory system that includes a memory controller, a plurality of memory channels in communication with the memory controller, an error detection code mechanism configured for detecting a failing memory channel, and an error recovery mechanism. The error recovery mechanism is configured for receiving notification of the failing memory channel, for performing a recovery operation on the failing memory channel while other memory channels are performing normal system operations, for bringing the recovered channel back into operational mode with the other memory channels for store operations, for continuing to mark the recovered channel to guard against stale data, for removing any stale data after the recovery operation is complete, and for removing the mark on the recovered channel to allow the normal system operations with all of the memory channels, the removing in response to the removing any stale data being complete.

Abstract: Embodiments relate to a method for bitline deletion include, based on detecting a high bitline error rate condition in the cache at a selected bitline address, wherein the high bitline error rate condition indicates a high rate of errors at the selected bitline address, activating the programmable switch in the cache. The method also includes, based on the programmable switch being activated and encountering an error associated with the selected bitline address, automatically deleting, by the computer system, one or more cache lines associated with subsequent errors in the cache regardless of an address of the subsequent errors based on the activated programmable switch, wherein the automatic line deletion indicates a line is unavailable.

Abstract: A technique for error detection is provided. A controller is configured to detect errors by using error correcting code (ECC), and a cache includes independent ECC words for storing data. The controller detects the errors in the ECC words for a wordline that is read. The controller detects a first error in a first ECC word on the wordline and a second error in a second ECC word on the wordline. The controller determines that the wordline is a failing wordline based on detecting the first error in the first ECC word and the second error in the second ECC word.

Abstract: A technique for error detection is provided. A controller is configured to detect errors by using error correcting code (ECC), and a cache includes independent ECC words for storing data. The controller detects the errors in the ECC words for a wordline that is read. The controller detects a first error in a first ECC word on the wordline and a second error in a second ECC word on the wordline. The controller determines that the wordline is a failing wordline based on detecting the first error in the first ECC word and the second error in the second ECC word.

Abstract: Embodiments relate to a computer system for bitline deletion, the system including a cache controller and cache. The system is configured to perform a method including detecting a first error when reading a first cache line, recording a first address of the first error, detecting a second error when reading a second cache line, recording a second address of the second error, comparing first and second bitline addresses, comparing the first and second wordline address, activating a bitline delete mode based on matching first and second bitline addresses and not matching first and second wordline addresses, detecting a third error when reading a third cache line, recording a third bitline address of the third error, comparing the second bitline address to the third bitline address and deleting a location corresponding to the third cache line based on the activated bitline delete mode and matching third and second bitline addresses.

Abstract: Embodiments relate to a method including detecting a first error when reading a first cache line, recording a first address of the first error, detecting a second error when reading a second cache line and recording a second address of the second error. Embodiments also include comparing the first and second bitline address, comparing the first and second wordline address, activating a bitline delete mode based on matching first and second bitline addresses and not matching the first and second wordline addresses, detecting a third error when reading a third cache line, recording a third bitline address of the third error, comparing the second bitline address to a third bitline address and deleting a location corresponding to the third cache line from available cache locations based on the activated bitline delete mode and the third bitline address matching the second bitline address.

Abstract: Embodiments relate to a method for bitline deletion include, based on detecting a high bitline error rate condition in the cache at a selected bitline address, wherein the high bitline error rate condition indicates a high rate of errors at the selected bitline address, activating the programmable switch in the cache. The method also includes, based on the programmable switch being activated and encountering an error associated with the selected bitline address, automatically deleting, by the computer system, one or more cache lines associated with subsequent errors in the cache regardless of an address of the subsequent errors based on the activated programmable switch, wherein the automatic line deletion indicates a line is unavailable.

Abstract: Failing bus lane detection using syndrome analysis, including a method for receiving a plurality of syndromes of an error detection code, the error detection code associated with a plurality of frames that have been transmitted on a bus that includes a plurality of lanes and is protected by the error detection code. The method includes performing for each of the lanes in each of the syndromes: decoding the syndrome under an assumption that the lane is a failing lane, the decoding outputting a decode result; determining if the decode result is a valid decode; and voting for the lane in response to determining that the decode result is a valid decode. A failing lane is then identified in response to the voting, with the failing lane being characterized by having more votes than at least one other lane on the bus.

Abstract: Error correction and detection in a redundant memory system including a a computer implemented method that includes receiving data including error correction code (ECC) bits, the receiving from a plurality of channels, each channel comprising a plurality of memory devices at memory device locations. The method also includes computing syndromes of the data; receiving a channel identifier of one of the channels; and removing a contribution of data received on the channel from the computed syndromes, the removing resulting in channel adjusted syndromes. The channel adjusted syndromes are decoded resulting in channel adjusted memory device locations of failing memory devices, the channel adjusted memory device locations corresponding to memory device locations.

Abstract: Correcting memory device (chip) and memory channel failures in the presence of known memory device failures. A memory channel failure is located and corrected, or alternatively up to c chip failures are corrected and up to d chip failures are detected in the presence of up to u chips that are marked as suspect. A first stage of decoding is performed that results in recovering an estimate of correctable errors affecting the data or in declaring an uncorrectable error state. When an uncorrectable error state is declared, a second stage of decoding is performed to attempt to correct u erasures and a channel error in M iterations where the channel location is changed in each iteration. A correctable error is declared in response to exactly one of the M iterations being successful.

Abstract: Channel marking is provided in a memory system that includes a first memory channel, a second memory channel, and error correction code (ECC) logic. The memory system is configured to perform a method that includes receiving a request to apply a first channel mark to the first memory channel and determining a priority level of the first channel mark. A request is received to apply a second channel mark to the second memory channel, and a priority level of the second mark is determined. It is determined that the priority level of the first channel mark is higher than the priority level of the second channel mark. The first channel mark is supplied to the ECC logic while blocking the second channel mark from the ECC logic.

Abstract: Channel marking is provided in a memory system that includes a memory channel with a plurality of memory devices. The memory devices are arranged into a first group of memory devices and a second group of memory devices. The memory system is configured to perform a method that includes determining that more than a threshold number of memory devices in the first group are failing. An error correction code (ECC) is configured to compensate for errors associated with memory devices in the first group on the memory channel and to perform error correction on errors associated with memory devices in the second group on the memory channel.

Abstract: Dynamic graduated memory device protection in redundant array of independent memory (RAIM) systems that include a plurality of memory devices is provided. A first severity level of a first failing memory device in the plurality of memory devices is determined. The first failing memory device is associated with an identifier used to communicate a location of the first failing memory device to an error correction code (ECC). A second severity level of a second failing memory device in the plurality of memory devices is determined. It is determined that the second severity level is higher than the first severity level. The identifier from the first failing memory device is removed based on determining that the second severity level is higher than the first severity level. The identifier is applied to the second failing memory device based on determining that the second severity level is higher than the first severity level.