System and method for near-instant unmapping and write-same in a log-structured storage cluster

Patent metadata

Field	Value
Publication number	US-11941287-B2
Application number	US-202016903709-A
Country	US
Kind code	B2
Filing date	Jun 17, 2020
Priority date	Jun 17, 2020
Publication date	Mar 26, 2024
Grant date	Mar 26, 2024

Abstract

A method, computer program product, and computer system for receiving, by a computing device, a Write-Same operation from a host for a range of logical block addresses of a destination. Data may be recorded in a buffer to indicate that the Write-Same operation is complete prior to completing the Write-Same operation. An acknowledgment may be sent to the host that the Write-Same operation is complete prior to flushing to a final destination. The Write-Same operation for the logical block addresses of the destination may be performed after sending the acknowledgment to the host that the Write-Same operation is complete.

First claim

What is claimed is:

1. A computer-implemented method comprising:
receiving, by a computing device, a Write-Same operation from a host for a range of logical block addresses of a destination;
recording data in a buffer to indicate that the Write-Same operation is complete prior to completing the Write-Same operation, where the recorded data in the buffer includes a record, wherein the record is configured to indicate the Write-Same operation is complete and is configured to indicate a copied block;
after recording data in the buffer along with the copied block, sending an instant acknowledgment to the host indicating that the Write-Same operation is complete prior to completing the Write-Same operation and prior to flushing to a final destination; and
performing the Write-Same operation for the logical block addresses of the destination after sending the instant acknowledgment to the host that the Write-Same operation is complete.

2. The computer-implemented method of claim 1 wherein the range of logical block addresses of the destination is maintained in-memory.

3. The computer-implemented method of claim 2 wherein the range of logical block addresses of the destination is maintained in an interval tree structure in-memory.

4. The computer-implemented method of claim 1 wherein performing the Write-Same operation for the logical block addresses of the destination includes flushing a data block for the range of logical block addresses after sending the instant acknowledgment to the host that the Write-Same operation is complete.

5. The computer-implemented method of claim 1 wherein the Write-Same operation is done atomically.

6. The computer-implemented method of claim 1 wherein the buffer is a ring buffer.

7. The computer-implemented method of claim 1 wherein the interval tree structure is a B-Tree.

8. A computer program product residing on a computer readable storage medium having a plurality of instructions stored thereon which, when executed across one or more processors, causes at least a portion of the one or more processors to perform operations comprising:
receiving a Write-Same operation from a host for a range of logical block addresses of a destination;
recording data in a buffer to indicate that the Write-Same operation is complete prior to completing the Write-Same operation, where the recorded data in the buffer includes a record, wherein the record is configured to indicate the Write-Same operation is complete and is configured to indicate a copied block;
after recording data in the buffer along with the copied block, sending an instant acknowledgment to the host indicating that the Write-Same operation is complete prior to completing the Write-Same operation and prior to flushing to a final destination; and
performing the Write-Same operation for the logical block addresses of the destination after sending the instant acknowledgment to the host that the Write-Same operation is complete.

9. The computer program product of claim 8 wherein the range of logical block addresses of the destination is maintained in-memory.

10. The computer program product of claim 9 wherein the range of logical block addresses of the destination is maintained in an interval tree structure in-memory.

11. The computer program product of claim 8 wherein performing the Write-Same operation for the logical block addresses of the destination includes flushing a data block for the range of logical block addresses after sending the instant acknowledgment to the host that the Write-Same operation is complete.

12. The computer program product of claim 8 wherein the Write-Same operation is done atomically.

13. The computer program product of claim 8 wherein the buffer is a ring buffer.

14. The computer program product of claim 8 wherein the interval tree structure is a B-Tree.

15. A computing system including one or more processors and one or more memories configured to perform operations comprising:
receiving a Write-Same operation from a host for a range of logical block addresses of a destination;
recording data in a buffer to indicate that the Write-Same operation is complete prior to completing the Write-Same operation, where the recorded data in the buffer includes a record, wherein the record is configured to indicate the Write-Same operation is complete and is configured to indicate a copied block;
after recording data in the buffer along with the copied block, sending an instant acknowledgment to the host indicating that the Write-Same operation is complete prior to completing the Write-Same operation and prior to flushing to a final destination; and
performing the Write-Same operation for the logical block addresses of the destination after sending the instant acknowledgment to the host that the Write-Same operation is complete.

16. The computing system of claim 15 wherein the range of logical block addresses of the destination is maintained in-memory.

17. The computing system of claim 16 wherein the range of logical block addresses of the destination is maintained in an interval tree structure in-memory.

18. The computing system of claim 15 wherein performing the Write-Same operation for the logical block addresses of the destination includes flushing a data block for the range of logical block addresses after sending the instant acknowledgment to the host that the Write-Same operation is complete.

19. The computing system of claim 15 wherein the Write-Same operation is done atomically.

20. The computing system of claim 15 wherein the buffer is a ring buffer.

Assignees

• Emc Ip Holding Co Llc

Inventors

• David Bar
• Gazit Ronen

Classifications

• G06F3/0656 Primary

  Data buffering arrangements · CPC title

• G06F3/0611

  in relation to response time · CPC title

• G06F3/0619

  in relation to data integrity, e.g. data losses, bit errors · CPC title

• G06F3/064

  Management of blocks · CPC title

• G06F3/0659

  Command handling arrangements, e.g. command buffers, queues, command scheduling · CPC title