Die-level monitoring in a storage cluster

• US 9,880,899 B2
• Filed: 05/14/2015
• Issued: 01/30/2018
• Est. Priority Date: 08/07/2014
• Status: Active Grant

• Current Assignee: Pure Storage, Inc.
• Original Assignee: Pure Storage, Inc.
• Inventors: Davis, John D., Hayes, John, Tan, Zhangxi, Kannan, Hari, Miladinovic, Nenad
• Primary Examiner(s): BRITT, CYNTHIA H
• Application Number:
  US14/712,756
• Publication Number:
  US 20160041873A1
• Time in Patent Office: 992 Days
• CPC Class Codes: G06F 11/076 by exceeding a count or rate limit, e.g. word- or bit count limit
• CPC Class Codes: G06F 11/1048 using arrangements adapted for a specific error detection or correction feature
• CPC Class Codes: G06F 11/1068 in sector programmable memories, e.g. flash disk G06F11/1072 takes precedence
• CPC Class Codes: G06F 12/0246 in block erasable memory, e.g. flash memory
• CPC Class Codes: G06F 16/182 Distributed file systems
• CPC Class Codes: G06F 16/1827 Management specifically adapted to NAS management of storage area networks [SAN] G06F3/067
• CPC Class Codes: G06F 2212/7207 management of metadata or control data
• CPC Class Codes: G06F 2212/7208 Multiple device management, e.g. distributing data over multiple flash devices
• CPC Class Codes: G06F 2212/7211 Wear leveling
• CPC Class Codes: G11C 16/349 Arrangements for evaluating degradation, retention or wearout, e.g. by counting erase cycles
• CPC Class Codes: G11C 2029/0409 Online test
• CPC Class Codes: G11C 2029/0411 Online error correction
• CPC Class Codes: G11C 29/44 Indication or identification of errors, e.g. for repair
• CPC Class Codes: G11C 29/52 Protection of memory contents; Detection of errors in memory contents

Abstract

In some embodiments, a method for die-level monitoring is provided. The method includes distributing user data throughout a plurality of storage nodes through erasure coding, wherein the plurality of storage nodes are housed within a chassis that couples the storage nodes. Each of the storage nodes has a non-volatile solid-state storage with non-volatile memory and the user data is accessible via the erasure coding from a remainder of the storage nodes in event of two of the storage nodes being unreachable. The method includes producing diagnostic information that diagnoses the non-volatile memory on a basis of per package, per die, per plane, per block, or per page, the producing performed by each of the plurality of storage nodes. The method includes writing the diagnostic information to a memory in the storage cluster.

Claims

1. A method for die-level monitoring in a storage cluster, comprising:

distributing user data throughout a plurality of storage nodes of the storage cluster through erasure coding, with each of the plurality of storage nodes having a processor and one or more non-volatile solid-state storages each having a controller;

performing, in the controller in one of the non-volatile solid-state storages, error correction of reads of a non-volatile memory;

forwarding error information, based at least in part on the error correction, from the controller in the one of the non-volatile solid-state storages to the processor of each of one or more of the plurality of storage nodes; and

combining, by the processor of each of the one or more of the plurality of storage nodes, the error information from the controller in the one of the non-volatile solid state storages with higher-level application data.

2. The method of claim 1, further comprising:

characterizing the non-volatile memory over time, based on diagnostic information regarding the non-volatile memory of the non-volatile solid-state storage of each of the plurality of storage nodes, as a result of the combining.

3. The method of claim 2, further comprising:

sending at least a portion of the diagnostic information from the storage cluster to a network.

4. The method of claim 1, further comprising:

biasing at least one of a read from or a write to the non-volatile memory, responsive to producing diagnostic information based on the combining.

5. The method of claim 2, further comprising:

tracking wear of a plurality of blocks of the non-volatile memory, based on the diagnostic information.

6. The method of claim 1, further comprising:

producing diagnostic information based on the combining,

wherein the error information is based at least in part on tracking bit errors per page or per codeword, each page having a plurality of codewords.

7. The method of claim 1, wherein the performing the error correction and the forwarding the error information comprises:

performing, in the controller in the non-volatile solid-state storage of each of the plurality of storage nodes, error correction of reads of the non-volatile memory; and

reporting incidents of the error correction, wherein diagnostic information is based on the incidents of the error correction.

8. The method of claim 1, further comprising:

determining to which of a plurality of blocks to write a portion of the user data, based on the diagnostic information.

9. The method of claim 1, wherein multiple chassis are coupled to define the storage cluster.

10. The method of claim 1, wherein the controller is a programmable logic device.