TRIM SUPPORT FOR A SOLID-STATE DRIVE IN A VIRTUALIZED ENVIRONMENT

• US 20140325141A1
• Filed: 04/30/2013
• Published: 10/30/2014
• Est. Priority Date: 04/30/2013
• Status: Active Grant

• Current Assignee: Vmware LLC (Broadcom, Inc.)
• Original Assignee: VMware, Inc. (Broadcom, Inc.)
• Inventors: PHELAN, Thomas A., LIU, Deng
• Granted Patent: US 9,983,992 B2
• Time in Patent Office: Days
• US Class Current: 711/112
• CPC Class Codes: G06F 12/0246 in block erasable memory, e.g. flash memory
• CPC Class Codes: G06F 12/10 Address translation
• CPC Class Codes: G06F 13/1668 Details of memory controller
• CPC Class Codes: G06F 2009/45579 I/O management, e.g. providing access to device drivers or storage
• CPC Class Codes: G06F 2212/1044 Space efficiency improvement
• CPC Class Codes: G06F 2212/151 Emulated environment, e.g. virtual machine
• CPC Class Codes: G06F 2212/214 Solid state disk
• CPC Class Codes: G06F 2212/657 Virtual address space management
• CPC Class Codes: G06F 2212/7205 Cleaning, compaction, garbage collection, erase control
• CPC Class Codes: G06F 2213/0032 Serial ATA [SATA]
• CPC Class Codes: G06F 2213/0036 Small computer system interface [SCSI]
• CPC Class Codes: G06F 3/0604 Improving or facilitating administration, e.g. storage management
• CPC Class Codes: G06F 3/064 Management of blocks
• CPC Class Codes: G06F 3/0652 Erasing, e.g. deleting, data cleaning, moving of data to a wastebasket
• CPC Class Codes: G06F 3/0664 at device level, e.g. emulation of a storage device or system
• CPC Class Codes: G06F 3/0679 Non-volatile semiconductor memory device, e.g. flash memory, one time programmable memory [OTP]
• CPC Class Codes: G06F 3/0688 Non-volatile semiconductor memory arrays
• CPC Class Codes: G06F 9/45558 Hypervisor-specific management and integration aspects
• CPC Class Codes: G11B 19/28 Speed controlling, regulating, or indicating G11B19/24 takes precedence

Abstract

A computer system that employs a solid-state memory device as a physical storage resource includes a hypervisor that is capable of supporting TRIM commands issued by virtual machines running in the computer system. When a virtual machine issues a TRIM command to its corresponding virtual storage device to invalidate data stored therein, the TRIM command is received at an interface layer in the hypervisor that translates the TRIM command to a SCSI command known as UMMAP. A SCSI virtualization layer converts the UNMAP command to a file system command to delete portions of the virtual storage device that is maintained as a file in the hypervisor'"'"'s file system. Upon receiving the delete commands, the hypervisor'"'"'s file system driver generates a TRIM command to invalidate the data stored in the solid-state memory device at locations corresponding to the portions of the file that are to be deleted.

Claims

1. In a computer system having a virtual machine executed therein and a hypervisor supporting execution of the virtual machine, a method of issuing commands to invalidate data blocks stored in a physical solid-state memory device, the method comprising:

receiving a command to invalidate a virtual data block, which is a data block of a virtual solid-state memory device that is mapped to a portion of the physical solid-state memory device;

translating the received command into an interim command to release the virtual data block; and

translating the interim command into a block operation to invalidate a physical data block, which is a data block of the physical solid-state memory device corresponding to the virtual data block.

2. The method of claim 1, wherein the command to invalidate the virtual data block comprises a TRIM command.

3. The method of claim 1, wherein translating the received command into an interim command comprises translating a TRIM command to an UNMAP command.

4. The method of claim 1, wherein translating the interim command into the block operation further comprises translating the interim command to a file system command to delete portions of a file that corresponds to the virtual solid-state memory device and translating the file system command to the block operation to invalidate the physical data block.

5. The method of claim 4, wherein the deleted portions of the file are mapped to the physical data block.

6. The method of claim 1, wherein the command to invalidate the virtual data block is received from the virtual machine.

7. The method of claim 1, wherein the hypervisor is configured with a virtual advanced host controller interface adapter, and said receiving the command and said translating the received command are performed by the virtual advanced host controller interface adapter.

8. The method of claim 1, further comprising exposing at least a portion of the physical solid-state memory device to a guest operating system as a virtual solid-state memory device using a virtual advanced host controller interface adapter.

9. The method of claim 8, further comprising receiving an inquiry from the virtual machine regarding a logical block device characteristic of the virtual solid-state memory device.

10. The method of claim 9, wherein one of the logical block device characteristics is a rotational rate of a recording medium of the logical block device.

11. A non-transitory computer readable storage medium comprising instructions executable by a virtualization software layer of a computer system having a virtual machine executed therein, to carry out a method of issuing commands to invalidate data blocks stored in a physical solid-state memory device, the method comprising:

receiving a command to invalidate a virtual data block, which is a data block of a virtual solid-state memory device that is mapped to a portion of the physical solid-state memory device;

translating the received command into an interim command to release the virtual data block; and

translating the interim command into a block operation to invalidate a physical data block, which is a data block of the physical solid-state memory device corresponding to the virtual data block.

12. The non-transitory computer readable storage medium of claim 11, wherein the command to invalidate the virtual data block comprises a TRIM command.

13. The non-transitory computer readable storage medium of claim 11, wherein translating the received command into an interim command comprises translating a TRIM command to an UNMAP command.

14. The non-transitory computer readable storage medium of claim 11, wherein translating the interim command into the block operation further comprises translating the interim command to a file system command to delete portions of a file that corresponds to the virtual solid-state memory device and translating the file system command to the block operation to invalidate the physical data block.

15. The non-transitory computer readable storage medium of claim 14, wherein the deleted portions of the file are mapped to the physical data block.

16. The non-transitory computer readable storage medium of claim 11, wherein the command to invalidate the virtual data block is received from the virtual machine.

17. A computer system having virtual machines executed therein and a hypervisor supporting execution of the virtual machines, the computer system comprising:

a processor and memory,

wherein the hypervisor is programmed to issue commands to release storage allocated to a logical block device by a storage device by performing the steps of;

receiving a command to invalidate a virtual data block, which is a data block of a virtual solid-state memory device that is mapped to a portion of the physical solid-state memory device;

translating the received command into an interim command to release the virtual data block; and

translating the interim command into a block operation to invalidate a physical data block, which is a data block of the physical solid-state memory device corresponding to the virtual data block.

18. The computer system of claim 17, wherein the hypervisor is configured with a virtual advanced host controller interface adapter, and said receiving the command and said translating the received command are performed by the virtual advanced host controller interface adapter.

19. The computer system of claim 17, wherein the hypervisor is configured with a virtual advanced host controller interface adapter for exposing at least a portion of the physical solid-state memory device to a guest operating system as a virtual solid-state memory device.

20. The computer system of claim 19, wherein the virtual advanced host controller interface is configured to, in response to receiving an inquiry from the virtual machine, provide a logical block device characteristic of the virtual solid-state memory device.