Heterogeneous recovery in a redundant memory system

• US 8,775,858 B2
• Filed: 03/11/2013
• Issued: 07/08/2014
• Est. Priority Date: 06/24/2010
• Status: Active Grant

• Current Assignee: Globalfoundries US Incorporated (GlobalFoundries, Inc.)
• Original Assignee: International Business Machines Corporation
• Inventors: Gower, Kevin C., Lastras-Montano, Luis A., Meaney, Patrick J., Papazova, Vesselina K., Stephens, Eldee
• Primary Examiner(s): TRUONG, LOAN
• Application Number:
  US13/793,363
• Publication Number:
  US 20130191683A1
• Time in Patent Office: 484 Days
• Field of Search: 714/2, 714/4.21, 714/43, 714/6.12
• US Class Current: 714/2
• CPC Class Codes: G06F 11/073 in a memory management context, e.g. virtual memory or cache management memory management G06F12/00; testing of static memory units G11C29/00
• CPC Class Codes: G06F 11/0793 Remedial or corrective actions recovery from an exception in an instruction pipeline G06F9/3861; by retry G06F11/1402; for recovering from a failure of a protocol instance or entity H04L69/40
• CPC Class Codes: G06F 11/1004 to protect a block of data words, e.g. CRC or checksum G06F11/1076 takes precedence; security arrangements for protecting computers or computer systems against unauthorized activity G06F21/00
• CPC Class Codes: G06F 11/108 Parity data distribution in semiconductor storages, e.g. in SSD
• CPC Class Codes: G06F 11/141 for bus or memory accesses
• CPC Class Codes: G06F 11/1604 where the fault affects the clock signals of a processing unit and the redundancy is at or within the level of clock signal generation hardware
• CPC Class Codes: G06F 11/1666 where the redundant component is memory or memory area
• CPC Class Codes: G06F 11/20 using active fault-masking, e.g. by switching out faulty elements or by switching in spare elements
• CPC Class Codes: G06F 11/2007 using redundant communication media
• CPC Class Codes: G06F 11/2053 where persistent mass storage functionality or persistent mass storage control functionality is redundant error detection or correction in information storage based on relative movement between record carrier and transducer G11B20/18
• CPC Class Codes: G06F 2211/1088 Scrubbing in RAID systems with parity

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.

Claims

1. A computer implemented method for detecting a failing memory channel and performing a recovery operation, the method comprising:

receiving a notification that a memory channel has failed, the memory channel one of a plurality of memory channels in a memory system;

performing the recovery operation on the failing memory channel while other memory channels are performing normal system operations, the recovery operation comprising performing clock calibration on the failing memory channel, and performing data calibration on the plurality of memory channels based on completion of the clock calibration on the failing memory channel;

removing any stale data based on the recovery operation being completed, the removing while the other memory channels are performing normal system operations; and

continuing normal system operations with all of the memory channels based on the removing any stale data being completed.

2. The method of claim 1, wherein there are five memory channels.

3. The method of claim 1, the recovery operation further comprising performing lane repair on a lane in the failing memory channel.

4. The method of claim 1, the recovery operation further comprising transmitting a failure alert to the memory controller.

5. The method of claim 1, the recovery operation further comprising performing a reset of the plurality of memory channels and an operation retry.