Abstract: Mirrored memory scrubbing is optimized to reduce system power consumption and increase system performance. A memory scrub operation scrubs a first portion of the mirrored memory to detect and correc soft errors. The scrub rate of a second portion of the mirrored memory is eliminated, minimized, or reduced, relative to the scrub rate of the first portion. The reduced scrub operation preserves power consumed in association with scrubbing the second portion.

Abstract: Mirrored memory scrubbing is optimized to reduce system power consumption and increase system performance. A memory scrub operation scrubs a first portion of the mirrored memory to detect and correct soft errors. The scrub rate of a second portion of the mirrored memory is eliminated, minimized, or reduced, relative to the scrub rate of the first portion. The reduced scrub operation preserves power consumed in association with scrubbing the second portion.

Abstract: A Local Timer Engine (LTE) is disclosed. For an initiator in a computing system, the LTE measures a respective time delay for each of a plurality of routes between the initiator and a plurality of destinations. For each of the plurality of routes, the LTE determines a respective timeout value based on the measured respective time delay for the route and determines a unique memory mapped address identifying the route. The initiator sends a request to the LTE for a timeout value. The LTE determines a proper timeout value and provides the proper timeout value to the initiator.

Abstract: An aspect includes a method for receiving a memory allocation request for a logical partition. Partition mirroring is enabled for the logical partition. Unscrubbed memory is allocated to both a first and a second copy of the logical partition, with the second copy of the logical partition mirroring the first copy of the logical partition. Scrubbing of the first and second copy of the logical partitions is initiated. Subsequent to initiating the scrubbing one of the first and second copy of the logical partition is selected and partition mirroring is disabled for the logical partition. The first copy of the logical partition is deallocated based on selecting the second copy of the logical partition. The second copy of the logical partition is deallocated based on selecting the first copy of the logical partition.

Abstract: An aspect includes memory error recovery in a memory system includes detecting an error condition within a memory chip of the memory system. A chip mark is applied to the memory chip to flag the error condition. An address range of the memory chip associated with the error condition is determined. Data are written from the address range of the memory chip to a cache memory. The chip mark is removed based on determining that all of the data from the address range have been written to the cache memory.

Abstract: An aspect includes a method for auto-disabling dynamic random access memory (DRAM) error checking based on a threshold. A method includes receiving data at a DRAM and executing error checking logic based on the data. The error checking logic detects and error condition in the data and it is determined, at the DRAM, whether detecting the error condition in the data causes an error threshold to be reached. The error checking logic is disabled at the DRAM in response to determining that detecting the error condition in the data causes the error the error threshold to be reached.

Abstract: A method comprising of allocating a main memory partition and a mirrored memory partition, a mirrored copy of the main memory partition, of a mirrored memory system for scrubbing. The method also comprises of dividing the main memory partition into a first main portion and a second main portion and dividing the mirrored memory partition into a first mirrored portion and a second mirrored portion. The method determines a full scrub cycle that only scrubs a portion of the main memory channel and a portion of the mirrored memory partition, the full scrub cycle including scrubbing a main scrub portion, one of the first and the second main portions, and a mirrored scrub portion, one of the first and the second mirrored portions. The method initiates the full scrub cycle which includes a combination of memory portions, equivalent to a memory address range of the main memory partition.

Abstract: A method comprising of allocating a main memory partition and a mirrored memory partition, a mirrored copy of the main memory partition, of a mirrored memory system for scrubbing. The method also comprises of dividing the main memory partition into a first main portion and a second main portion and dividing the mirrored memory partition into a first mirrored portion and a second mirrored portion. The method determines a full scrub cycle that only scrubs a portion of the main memory channel and a portion of the mirrored memory partition, the full scrub cycle including scrubbing a main scrub portion, one of the first and the second main portions, and a mirrored scrub portion, one of the first and the second mirrored portions. The method initiates the full scrub cycle which includes a combination of memory portions, equivalent to a memory address range of the main memory partition.

Abstract: A method comprising of allocating a main memory partition and a mirrored memory partition, a mirrored copy of the main memory partition, of a mirrored memory system for scrubbing. The method also comprises of dividing the main memory partition into a first main portion and a second main portion and dividing the mirrored memory partition into a first mirrored portion and a second mirrored portion. The method determines a full scrub cycle that only scrubs a portion of the main memory channel and a portion of the mirrored memory partition, the full scrub cycle including scrubbing a main scrub portion, one of the first and the second main portions, and a mirrored scrub portion, one of the first and the second mirrored portions. The method initiates the full scrub cycle which includes a combination of memory portions, equivalent to a memory address range of the main memory partition.

Abstract: An aspect includes a method for auto-disabling dynamic random access memory (DRAM) error checking based on a threshold. A method includes receiving data at a DRAM from a memory controller and executing error checking logic based on the data. The error checking logic detects an error condition in the data and it is determined, at the DRAM, whether detecting the error condition in the data causes an error threshold to be reached. The error checking logic is disabled at the DRAM in response to determining that detecting the error condition in the data causes the error the error threshold to be reached. The error condition is communicated to the memory controller in response to determining that detecting the error condition does not cause the error threshold to be reached.

Abstract: An aspect includes memory error recovery in a memory system includes detecting an error condition within a memory chip of the memory system. A chip mark is applied to the memory chip to flag the error condition. An address range of the memory chip associated with the error condition is determined. Data are written from the address range of the memory chip to a cache memory. The chip mark is removed based on determining that all of the data from the address range have been written to the cache memory.

Abstract: An aspect includes a method for receiving a memory allocation request for a logical partition. Partition mirroring is enabled for the logical partition. Unscrubbed memory is allocated to both a first and a second copy of the logical partition, with the second copy of the logical partition mirroring the first copy of the logical partition. Scrubbing of the first and second copy of the logical partitions is initiated. Subsequent to initiating the scrubbing one of the first and second copy of the logical partition is selected and partition mirroring is disabled for the logical partition. The first copy of the logical partition is deallocated based on selecting the second copy of the logical partition. The second copy of the logical partition is deallocated based on selecting the first copy of the logical partition.

Abstract: Confirming memory marks indicating an error in computer memory including detecting, by memory logic responsive to a memory read operation, an error in at a memory location; marking, by the memory logic in an entry in a hardware mark table, the memory location as containing the error, the entry including one or more parameters for correcting the error; and retrying, by the memory logic, the memory read operation, including: responsive to again detecting the error in the memory location, determining whether the error is correctable at the memory location using the parameters included in the entry; and if the error is correctable at the memory location using the one or more parameters included in the entry, confirming the error in the entry of the hardware mark table.

Abstract: Performing error correction in computer memory including receiving a read request targeting a read address within the computer memory; accessing a mark table comprising a plurality of entries, each entry including a field specifying a region size, a field specifying a match address, and a field specifying a mark location; performing a lookup of the mark table using the read address including, for each entry in the mark table: generating a mask based on the region size stored in the entry; determining, based on the mask, whether the read address is within a memory region specified by the match address and region size stored in the entry; and if the read address is within the memory region specified by the match address and region size stored in the entry, performing error correction using the mark location stored in the entry.

Abstract: Mirrored memory scrubbing is optimized to reduce system power consumption and increase system performance. A memory scrub operation scrubs a first portion of the mirrored memory to detect and correct soft errors. The scrub rate of a second portion of the mirrored memory is eliminated, minimized, or reduced, relative to the scrub rate of the first portion. The reduced scrub operation preserves power consumed in association with scrubbing the second portion.

Abstract: A system and method of performing selective error coding in memory management of a memory device are described. The method includes performing a process of detecting and correcting memory errors in the memory of the memory device either prior to or after a chip mark associated with the memory device is in place. The method also includes localizing hard errors of the memory device based on a second process of detecting the memory errors in the memory of the memory device, the hard errors being persistent memory errors that persist from the process of detecting and correcting the memory errors to the second process, determining an extent of the hard errors based on the localizing, and preventing placement of the chip mark or removing the chip mark after de-allocating one or more ranges of addresses based on a result of the determining the extent of the hard errors.

Abstract: Mirrored memory scrubbing is optimized to reduce system power consumption and increase system performance. A memory scrub operation scrubs a first portion of the mirrored memory to detect and correct soft errors. The scrub rate of a second portion of the mirrored memory is eliminated, minimized, or reduced, relative to the scrub rate of the first portion. The reduced scrub operation preserves power consumed in association with scrubbing the second portion.

Abstract: Tracking address ranges for computer memory errors including detecting, by memory logic, an error at a memory address, the memory address representing one or more memory cells at a physical location of computer memory; reporting, by the memory logic to memory firmware, the detected error including providing the memory firmware with the memory address; identifying, by the memory firmware, an address range affected by the detected error including scanning the computer memory in dependence upon the memory address; determining, by the memory firmware, a region size based on the address range affected by the detected error; and populating an entry in a mark table corresponding to the detected error, including populating a field specifying the region size and a field specifying a match address corresponding to the memory address.

Abstract: Managing entries in a mark table of computer memory errors including identifying at least two mark table entries as candidates for merger, wherein each mark table entry indicates an error at a location in a computer memory; and merging the identified mark table entries into a single mark table entry, including removing one of the identified mark table entries from the mark table.

Abstract: An aspect includes memory error recovery in a memory system includes detecting an error condition within a memory chip of the memory system. A chip mark is applied to the memory chip to flag the error condition. An address range of the memory chip associated with the error condition is determined. Data are written from the address range of the memory chip to a cache memory. The chip mark is removed based on determining that all of the data from the address range have been written to the cache memory.