STORAGE ARRAY CONTROLLER FOR SOLID-STATE STORAGE DEVICES

• US 20120059976A1
• Filed: 09/07/2010
• Published: 03/08/2012
• Est. Priority Date: 09/07/2010
• Status: Abandoned Application

• Current Assignee: Daniel L. Rosenband
• Original Assignee: Daniel L. Rosenband
• Inventors: Rosenband, Daniel L., Smith, Michael John Sebastian
• Application Number:
  US12/876,393
• Publication Number:
  US 20120059976A1
• Time in Patent Office: Days
• US Class Current: 711/103
• CPC Class Codes: G06F 12/0246 in block erasable memory, e.g. flash memory
• CPC Class Codes: G06F 12/0253 Garbage collection, i.e. reclamation of unreferenced memory
• CPC Class Codes: G06F 2212/7205 Cleaning, compaction, garbage collection, erase control
• CPC Class Codes: G06F 3/061 Improving I/O performance
• CPC Class Codes: G06F 3/0659 Command handling arrangements, e.g. command buffers, queues, command scheduling
• CPC Class Codes: G06F 3/0688 Non-volatile semiconductor memory arrays

Abstract

A storage array controller provides a method and system for autonomously issuing trim commands to one or more solid-state storage devices in a storage array. The storage array controller is separate from any operating system running on a host system and separate from any controller in the solid-state storage device(s). The trim commands allow the solid-state storage device to operate more efficiently.

Claims

1. A method of managing a storage array comprising:

a storage array controller that is operable to receive one or more host commands from an operating system;

wherein the one or more host commands are directed to one or more solid-state storage devices in the storage array;

wherein the storage array controller is operable to generate one or more disk trim commands in response to the one or more host commands;

wherein the generating one or more disk trim commands is performed in an autonomous manner; and

wherein the one or more disk trim commands are directed to at least one of the one or more solid-state storage devices.

2. The method of claim 1 wherein the operating system is not operable for generating the one or more disk trim commands.

3. The method of claim 1 wherein the generating one or more disk trim commands further comprises merging one or more host trim commands into the one or more disk trim commands.

4. The method of claim 1 wherein the receiving host commands further comprises:

updating a map from a plurality of host block addresses to a plurality of array block addresses; and

placing one or more old array block addresses in the one or more disk trim commands.

5. The method of claim 1 wherein the managing a storage array is performed in software.

6. The method of claim 1 wherein the managing a storage array is performed in software in a hypervisor.

7. The method of claim 1 wherein the managing a storage array further comprises:

maintaining one or more maps and one or more freelists;

performing garbage collection on at least one of the one or more maps and one or more freelists as a result of the receiving of the one or more host commands;

generating one or more superblocks; and

placing one or more superblock addresses of the one or more superblocks in the one or more disk trim commands.

8. A storage array controller operable to be coupled to a host system and a storage array;

wherein the storage array includes a plurality of storage devices;

wherein the plurality of storage devices includes at least one solid-state storage device;

wherein the storage array controller is operable to receive host commands from the host system; and

wherein the storage array controller is operable to autonomously issue a disk trim command to the at least one solid-state storage device.

9. The storage array controller of claim 8 wherein the storage array controller maintains a map and a freelist;

wherein the map converts host block addresses to array block addresses; and

wherein the freelist includes a plurality of free array block addresses.

10. The storage array controller of claim 9 wherein the storage array controller is operable to place one or more of the plurality of free array block addresses in the disk trim command.

11. The storage array controller of claim 9 wherein the storage array controller issues a disk trim command to array block addresses that are not in the map.

12. The storage array controller of claim 9 wherein the storage array controller creates one or more old array block addresses;

and wherein the storage array controller issues disk trim commands to the one or more old array block addresses.

13. The storage array controller of claim 9 wherein the storage array controller performs garbage collection.

14. The storage array controller of claim 9 wherein the storage array controller collects write commands into one or more superblocks;

and wherein the storage array controller writes to one or more of the at least one solid-state disks using the one or more superblocks.

15. The storage array controller of claim 8 wherein the disk trim command is generated in a device driver.

16. The storage array controller of claim 15 wherein the device driver is part of a host system.

17. The storage array controller of claim 15 wherein the device driver is part of a hypervisor.

18. The storage array controller of claim 8 wherein the storage capacity presented to the host system (C1) is less than the storage array capacity (C2);

wherein the storage array capacity (C2) minus the storage capacity presented to the host system (C1) is a portion of storage capacity (C2−

C1); and

wherein the storage array controller autonomously issues a trim command to the portion of storage capacity (C2−

C1).

19. The storage array controller of claim 8 wherein the storage array controller issues a disk trim command during an operation selected from the following:

storage array initialization, storage array creation, storage array resizing, LUN creation, LUN removal, LUN resizing, LUN deletion.

20. A computer system for storing and providing data;

the computer system operable to be coupled to a storage array controller;

the storage array controller operable to be coupled to a storage array;

the storage array including a plurality of storage devices;

the plurality of storage devices including at least one solid-state storage devices; and

wherein the storage array controller is operable to autonomously issue a disk trim command to one or more of the at least one solid-state storage devices.