Memory system power management

Patent metadata

Field	Value
Publication number	US-10168936-B2
Application number	US-201715818789-A
Country	US
Kind code	B2
Filing date	Nov 21, 2017
Priority date	Apr 21, 2016
Publication date	Jan 1, 2019
Grant date	Jan 1, 2019

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.

First claim

The invention claimed is:

1. A method of power management in a memory of a computer system, the method comprising:
receiving a memory allocation request for a logical partition;
enabling partition mirroring for the logical partition;
allocating unscrubbed memory to both a first and a second copy of the logical partition, the second copy of the logical partition mirroring the first copy of the logical partition;
initiating scrubbing of the first and second copy of the logical partition; and
subsequent to initiating the scrubbing:
selecting one of the first and second copy of the logical partition, wherein prior to the selecting, the scrubbing is performed until a number of errors detected in at least one of the first copy of the logical partition and the second copy of the logical partition is less than a threshold number of errors;
disabling partition mirroring for the logical partition;
deallocating the first copy of the logical partition based on selecting the second copy of the logical partition; and
deallocating the second copy of the logical partition based on selecting the first copy of the logical partition.

2. The method of claim 1 , wherein the selecting is based on a number of errors detected during the scrubbing.

3. The method of claim 2 , wherein the first copy of the logical partition is selected based on the first copy of the logical partition having a same or fewer number of errors detected during the scrubbing than the second copy of the logical partition, and the second copy of the logical partition is selected based on the second copy of the logical partition having a fewer number of errors detected during the scrubbing than the first copy of the logical partition.

4. The method of claim 1 , wherein prior to the selecting, the scrubbing is performed for a predetermined time period.

5. The method of claim 1 , wherein the memory includes a dynamic random-access memory.

6. The method of claim 1 , wherein errors detected in the first copy of the logical partition during the scrubbing are corrected based on contents of the second copy of the logical partition.

7. The method of claim 1 , wherein the deallocating of the first copy of the logical partition includes halting scrubbing of the first copy of the logical partition.

8. A computer system comprising:
a processor; and
program code configured to be executed by the processor to:
receive a memory allocation request for a logical partition;
enable partition mirroring for the logical partition;
allocate unscrubbed memory to both a first and a second copy of the logical partition, the second copy of the logical partition mirroring the first copy of the logical partition;
initiate scrubbing of the first and second copy of the logical partition; and
subsequent to initiating the scrubbing:
selecting one of the first and second copy of the logical partition, wherein prior to the selecting, the scrubbing is performed until a number of errors detected in at least one of the first copy of the logical partition and the second copy of the logical partition is less than a threshold number of errors;
disabling partition mirroring for the logical partition;
deallocating the first copy of the logical partition based on selecting the second copy of the logical partition; and
deallocating the second copy of the logical partition based on selecting the first copy of the logical partition.

9. The computer system of claim 8 , wherein the selecting is based on a number of errors detected during the scrubbing in the first and second copies of the logical partition.

10. The computer system of claim 9 , wherein the first copy of the logical partition is selected based on the first copy of the logical partition having a same or fewer number of errors detected during the scrubbing than the second copy of the logical partition, and the second copy of the logical partition is selected based on the second copy of the logical partition having a fewer number of errors detected during the scrubbing than the first copy of the logical partition.

11. The computer system of claim 8 , wherein prior to the selecting, the scrubbing is performed for a predetermined time period.

12. The computer system of claim 8 , wherein the memory includes a dynamic random-access memory.

13. The computer system of claim 8 , wherein errors detected in the first copy of the logical partition during the scrubbing are corrected based on contents of the second copy of the logical partition.

14. The computer system of claim 8 , wherein the deallocating of the first copy of the logical partition includes halting scrubbing of the first copy of the logical partition.

15. A computer program product for power management in a memory of a computer system, the computer program product comprising a non-transitory computer readable storage medium having program instructions embodied therewith, the program instructions executable by processing circuitry to cause the processing circuitry to:
receive a memory allocation request for a logical partition;
enable partition mirroring for the logical partition;
allocate unscrubbed memory to both a first and a second copy of the logical partition, the second copy of the logical partition mirroring the first copy of the logical partition;
initiate scrubbing of the first and second copy of the logical partition; and
subsequent to initiating the scrubbing:
selecting one of the first and second copy of the logical partition, wherein prior to the selecting, the scrubbing is performed until a number of errors detected in at least one of the first copy of the logical partition and the second copy of the logical partition is less than a threshold number of errors;
disabling partition mirroring for the logical partition;
deallocating the first copy of the logical partition based on selecting the second copy of the logical partition; and
deallocating the second copy of the logical partition based on selecting the first copy of the logical partition.

16. The computer program product of claim 15 , wherein the selecting is based on a number of errors detected during the scrubbing in the first and second copies of the logical partition.

17. The computer program product of claim 15 , wherein the first copy of the logical partition is selected based on the first copy of the logical partition having a same or fewer number of errors detected during the scrubbing than the second copy of the logical partition, and the second copy of the logical partition is selected based on the second copy of the logical partition having a fewer number of errors detected during the scrubbing than the first copy of the logical partition.

18. The computer program product of claim 15 , wherein prior to the selecting, the scrubbing is performed for a predetermined time period.

19. The computer program product of claim 15 , wherein the memory includes a dynamic random-access memory.

20. The computer program product of claim 15 , wherein errors detected in the first copy of the logical partition during the scrubbing are corrected based on contents of the second copy of the logical partition.

Assignees

• IBM

Inventors

• Chinnakkonda Vidyapoornachary Diyanesh B
• Gollub Marc A
• Sawan Tony E

Classifications

• G06F3/0619

  in relation to data integrity, e.g. data losses, bit errors · CPC title

• G06F3/0625 Primary

  Power saving in storage systems · CPC title

• G06F3/0652

  Erasing, e.g. deleting, data cleaning, moving of data to a wastebasket · CPC title

• G11C29/12

  Built-in arrangements for testing, e.g. built-in self testing [BIST] {or interconnection details} · CPC title

• G06F3/0679

  Non-volatile semiconductor memory device, e.g. flash memory, one time programmable memory [OTP] · CPC title