Redundancy Coding Stripe Based On Internal Addresses Of Storage Devices

Patent metadata

Field	Value
Publication number	US-2019102250-A1
Application number	US-201715722685-A
Country	US
Kind code	A1
Filing date	Oct 2, 2017
Priority date	Oct 2, 2017
Publication date	Apr 4, 2019
Grant date	—

Abstract

Technology disclosed herein efficiently uses memory available in non-volatile storage devices in a non-volatile memory system. In one aspect, a manager collects enough data to fill an entire chunk of a redundancy coding stripe, and requests that the entire chunk be written together in a selected non-volatile storage device. The selected non-volatile storage device may return an internal address at which the entire chunk was written. The manager may store a stripe map that identifies the internal addresses at which each chunk was stored.

First claim

What is claimed is:

1 . A system comprising:
non-transitory storage; a data collecting module configured to collect, for each chunk of a redundancy coding stripe, data for the chunk; a command module configured to issue a command to write the data for the chunk of the redundancy coding stripe in a selected of a plurality of non-volatile storage devices; an interface configured to receive, for each chunk of the redundancy coding stripe, an internal address of the chunk in the selected non-volatile storage device; and a redundancy coding module configured to store into the non-transitory storage a redundancy stripe map having a redundancy stripe identifier and the internal addresses in the non-volatile storage devices for the chunks of the redundancy coding stripe.

2 . The system of claim 1 , further comprising a data recovery module configured to:
send a request to a first of the non-volatile storage devices for a chunk of the redundancy coding stripe, the request specifies the internal address of the chunk.

3 . The system of claim 1 , further comprising logic configured to instruct at least one of the plurality of non-volatile storage devices to store, into non-volatile storage, a forward map that maps from virtual addresses to redundancy stripe identifiers.

4 . The system of claim 3 , further comprising a data recovery module configured to:
read the forward map from the non-volatile storage on a non-volatile storage device to retrieve a redundancy stripe identifier for a virtual address; use the retrieved redundancy stripe identifier to retrieve internal addresses in the redundancy stripe map; and request chunks of data from ones of the non-volatile storage devices, the requests for the chunks specifying the retrieved internal addresses.

5 . The system of claim 1 , wherein each of the chunks of data comprise a plurality of blocks of random data each with an external logical address, and wherein a first of the non-volatile storage devices comprises:
an address mapping module configured to:
map the external logical addresses associated with a chunk of data to sequential internal addresses in the first non-volatile storage device; and
store the mapping in non-transitory storage in the first non-volatile storage device.

6 . The system of claim 1 , wherein a first of the non-volatile storage devices comprises:
writing logic configured to write the entire chunk of the redundancy coding stripe to a contiguous region of non-volatile memory cells in the first non-volatile storage device; and address providing logic configured to provide, to the interface, an internal address at which the chunk was written in the first non-volatile storage device.

7 . The system of claim 1 , wherein the internal address that a first of the plurality of non-volatile storage devices provides for a first chunk in the redundancy coding stripe is a first internal logical address.

8 . The system of claim 7 , wherein the first non-volatile storage device further comprises:
non-transitory storage; writing logic configured to move the first chunk that is stored in a first contiguous region in the first non-volatile storage device to a second contiguous region in the first non-volatile storage device; and an address mapping module configured to update, in the non-transitory storage, a mapping of the first internal logical address from the first contiguous region to the second contiguous region.

9 . The system of claim 8 , wherein the first contiguous region is all or a portion of a first erase block in the first non-volatile storage device, wherein the second contiguous region is all or a portion of a second erase block in the first non-volatile storage device.

10 . The system of claim 1 , wherein each of the chunks of data comprise a plurality of blocks of random data each with an external logical block address, and further comprising drive virtualization logic configured to:
for each virtual block address associated with one of the external logical block addresses sent in a write request to one of the plurality of non-volatile storage devices, convert the virtual block address to one of the external logical block addresses and an identifier of one of the plurality of non-volatile storage devices.

11 . The system of claim 1 , wherein the command to write the data for the chunk of the redundancy coding stripe in the selected one of the plurality of non-volatile storage devices instructs the selected non-volatile storage device to write the entire chunk within all or a portion of an erase block.

12 . A method comprising:
receiving, at each of a plurality of non-volatile storage devices, a request to write a chunk of a redundancy coding stripe; writing, by each of the non-volatile storage devices, the entire chunk to a contiguous region of non-volatile memory cells in the respective non-volatile storage device; providing, by each of the non-volatile storage devices, a fixed internal address of the chunk in an internal address space of the respective non-volatile storage device; and storing a redundancy stripe map into non-transitory storage, the redundancy stripe map having a redundancy stripe identifier and the fixed internal addresses for the chunks for the redundancy coding stripe.

13 . The method of claim 12 , further comprising:
sending a request to a first of the non-volatile storage devices for a chunk of the redundancy coding stripe, the request specifies the fixed internal address of the chunk.

14 . The method of claim 13 , further comprising:
instructing at least one of the plurality of non-volatile storage devices to store, into non-volatile storage, a forward map that maps from virtual addresses to redundancy stripe identifiers.

15 . The method of claim 14 , further comprising:
reading the forward map from the non-volatile storage on a non-volatile storage device to retrieve a redundancy stripe identifier for a virtual address; using the retrieved redundancy stripe identifier to retrieve internal addresses in the redundancy stripe map; and requesting chunks of data from ones of the non-volatile storage devices, the requests for the chunks specifying the retrieved internal addresses.

16 . The method of claim 12 , further comprising:
collecting, by a manager system, random writes for each of the chunks of the redundancy coding stripe; and sending, by the manager system, commands to write all of the random writes for each of the chunks in a contiguous region on each of the non-volatile storage devices.

17 . The method of claim 16 , wherein the contiguous region is an erase block.

18 . A non-volatile storage system comprising:
non-transitory storage; data collecting means for collecting random writes for each chunk of a redundancy coding stripe; command means for sending, to each of a plurality of non-volatile storage devices, a command to write one of the chunks of random writes within a contiguous region of the non-volatile storage device; writing means for writing each respective chunk of the redundancy coding stripe in a contiguous region of non-volatile memory cells in each respective non-volatile storage device; address providing means for providing, for each of the chunks, an internal address at which the chunk was written in the respective non-volatile storage device; and redundancy coding means for storing into the non-transitory storage a redundancy stripe map having a redundancy stripe identifier and the internal addresses for the chunks for the redundancy coding stripe.

Assignees

• Western Digital Tech Inc

Inventors

• O'Krafka Brian W
• Bolkhovitin Vladislav
• Subbarao Sanjay

Classifications

• G11C29/52 Primary

  Protection of memory contents; Detection of errors in memory contents · CPC title

• G06F2212/7208

  Multiple device management, e.g. distributing data over multiple flash devices · CPC title

• G06F2212/657

  Virtual address space management · CPC title

• G06F11/1068 Primary

  in sector programmable memories, e.g. flash disk (G06F11/1072 takes precedence) · CPC title

• G06F12/109

  for multiple virtual address spaces, e.g. segmentation (G06F12/1036 takes precedence) · CPC title