TIER-OPTIMIZED WRITE SCHEME

• US 20180129426A1
• Filed: 06/20/2017
• Published: 05/10/2018
• Est. Priority Date: 04/13/2015
• Status: Active Grant

• Current Assignee: Cohesity, Inc.
• Original Assignee: Cohesity, Inc.
• Inventors: Aron, Mohit, Shanmuganathan, Ganesha
• Granted Patent: US 10,120,587 B2
• Time in Patent Office: Days
• CPC Class Codes: G06F 12/0238 Memory management in non-volatile memory, e.g. resistive RAM or ferroelectric memory
• CPC Class Codes: G06F 12/08 in hierarchically structured memory systems, e.g. virtual memory systems
• CPC Class Codes: G06F 2212/1016 Performance improvement
• CPC Class Codes: G06F 2212/217 Hybrid disk, e.g. using both magnetic and solid state storage devices
• CPC Class Codes: G06F 3/0611 in relation to response time
• CPC Class Codes: G06F 3/0643 Management of files
• CPC Class Codes: G06F 3/0656 Data buffering arrangements
• CPC Class Codes: G06F 3/0673 Single storage device
• CPC Class Codes: G06F 3/0685 Hybrid storage combining heterogeneous device types, e.g. hierarchical storage, hybrid arrays

Abstract

Techniques are disclosed for storing data in a plurality of storage tiers on a computing node. A node receives a request to write data corresponding to at least a first portion of a file. The node determines whether to perform the request either as an in-place write or as an out-of-place write. Upon determining to perform the request as the in-place write, the node writes the data to a first location on a storage tier which currently stores the first portion of the file. Upon determining to perform the request as the out-of-place write, the node writes the data to a second location on one of the storage tiers, other than the first location.

Claims

1. A method for storing data, the method comprising:

receiving a request to write data corresponding to at least a first portion of a file;

determining whether to perform the request either as an in-place write or as an out-of-place write, wherein performing the in-place write comprises performing a write to a low latency storage device and performing the out-of-place write comprises performing a write to a higher latency storage device;

in an event it is determined to perform the request as the in-place write, writing the data to a first location on a storage tier which currently stores the first portion of the file; and

in an event it is determined to perform the request as the out-of-place write, writing the data to a second location on one of a plurality of storage tiers of a computing node, other than the first location.

2. The method of claim 1, wherein determining to perform the request as the out-of-place write comprises:

determining that the first portion of the file corresponds to a deduplicated portion.

3. The method of claim 1, wherein determining to perform the request as the out-of-place write comprises:

determining that the first portion of the file corresponds to a compressed group of portions from one or more files.

4. The method of claim 1, further comprising:

recording a pattern of input/output operations to one or more portions of the file.

5. The method of claim 4, further comprising:

determining, based on the recorded pattern of the input/output operations, whether to perform the request as either the in-place write or as the out-of-place write.

6. The method of claim 5, wherein determining, based on the recorded pattern of the input/output operations, whether to perform the request as the out-of-place write comprises:

determining that the recorded pattern of input/output operations corresponds to a sequential pattern of input/output operations.

7. The method of claim 5, further comprising:

determining, based on the recorded pattern of the input/output operations, whether to write the data to the first location on the storage tier which currently stores the first portion of the file or to the second location on one of the storage tiers, other than the first location.

8. The method of claim 1, wherein the computing node is a node of a secondary storage system.

9. A computer program product for storing data, the computer program product being embodied in a non-transitory computer readable storage medium and comprising computer instructions for:

receiving a request to write data corresponding to at least a first portion of a file;

determining whether to perform the request either as an in-place write or as an out-of-place write, wherein performing the in-place write comprises performing a write to a low latency storage device and performing the out-of-place write comprises performing a write to a higher latency storage device;

in an event it is determined to perform the request as the in-place write, writing the data to a first location on a storage tier which currently stores the first portion of the file; and

in an event it is determined to perform the request as the out-of-place write, writing the data to a second location on one of a plurality of storage tiers of a computing node, other than the first location.

10. The computer program product of claim 9, wherein determining to perform the request as the out-of-place write comprises:

determining that the first portion of the file corresponds to a deduplicated portion.

11. The computer program product of claim 9, wherein determining to perform the request as the out-of-place write comprises:

determining that the first portion of the file corresponds to a compressed group of portions from one or more files.

12. The computer program product of claim 9, further comprising computer instructions for:

recording a pattern of input/output operations to one or more portions of the file.

13. The computer program product of claim 12, further comprising computer instructions for:

determining, based on the recorded pattern of the input/output operations, whether to perform the request as either the in-place write or as the out-of-place write.

14. The computer program product of claim 13, wherein determining, based on the recorded pattern of the input/output operations, whether to perform the request as the out-of-place write comprises:

determining that the recorded pattern of input/output operations corresponds to a sequential pattern of input/output operations.

15. A system, comprising:

a processor; and

a memory coupled with the processor, wherein the memory is configured to provide the processor with instructions which when executed cause the processor to;

receive a request to write data corresponding to at least a first portion of a file;

determine whether to perform the request either as an in-place write or as an out-of-place write, wherein performing the in-place write comprises performing a write to a low latency storage device and performing the out-of-place write comprises performing a write to a higher latency storage device;

in an event it is determined to perform the request as the in-place write, write the data to a first location on a storage tier which currently stores the first portion of the file; and

in an event it is determined to perform the request as the out-of-place write, write the data to a second location on one of a plurality of storage tiers of a computing node, other than the first location.

16. The system of claim 15, wherein determining to perform the request as the out-of-place write comprises:

determining that the first portion of the file corresponds to a deduplicated portion.

17. The system of claim 15, wherein determining to perform the request as the out-of-place write comprises:

determining that the first portion of the file corresponds to a compressed group of portions from one or more files.

18. The system of claim 15, wherein the memory is further configured to provide the processor with instructions which when executed cause the processor to:

record a pattern of input/output operations to one or more portions of the file; and

determine, based on the recorded pattern of the input/output operations, whether to perform the request as either the in-place write or as the out-of-place write.

19. The system of claim 18, wherein determining, based on the recorded pattern of the input/output operations, whether to perform the request as the out-of-place write comprises:

determining that the recorded pattern of input/output operations corresponds to a sequential pattern of input/output operations.

20. The system of claim 15, wherein the computing node is a node of a secondary storage system.