Method and system supporting per-file and per-block replication

• US 20070106851A1
• Filed: 04/19/2006
• Published: 05/10/2007
• Est. Priority Date: 11/04/2005
• Status: Active Grant

• Current Assignee: Oracle America, Inc. (Oracle Corporation)
• Original Assignee: Sun Microsystems Incorporated (Oracle Corporation)
• Inventors: Moore, William, Bonwick, Jeffrey
• Granted Patent: US 7,873,799 B2
• Time in Patent Office: Days
• US Class Current: 711/154
• CPC Class Codes: G06F 11/1076 Parity data used in redundant arrays of independent storages, e.g. in RAID systems
• CPC Class Codes: G06F 11/1435 using file system or storage system metadata
• CPC Class Codes: G06F 11/2056 by mirroring
• CPC Class Codes: G06F 16/184 implemented as replicated file system
• CPC Class Codes: G06F 2003/0697 device management, e.g. handlers, drivers, I/O schedulers
• CPC Class Codes: G06F 2211/105 On the fly coding, e.g. using XOR accumulators
• CPC Class Codes: G06F 3/0601 Interfaces specially adapted for storage systems
• CPC Class Codes: G06F 3/0604 Improving or facilitating administration, e.g. storage management
• CPC Class Codes: G06F 3/0643 Management of files
• CPC Class Codes: G06F 3/0644 Management of space entities, e.g. partitions, extents, pools
• CPC Class Codes: G06F 3/065 Replication mechanisms
• CPC Class Codes: G06F 3/0689 Disk arrays, e.g. RAID, JBOD

Abstract

A method for writing data to a storage pool, involving receiving a first write operation to write a first block to the storage pool, determining a first replication type for the first block using a first replication policy associated with the first block, determining a first number of physical blocks required to write the first block to the storage pool using a size of the first block and the first replication type, and writing the first block, in accordance with the first replication policy, to the storage pool by filling in the first number of physical blocks.

Claims

1. A method for writing data to a storage pool, comprising:

receiving a first write operation to write a first block to the storage pool;

determining a first replication type for the first block using a first replication policy associated with the first block;

determining a first number of physical blocks required to write the first block to the storage pool using a size of the first block and the first replication type; and

writing the first block, in accordance with the first replication policy, to the storage pool by filling in the first number of physical blocks.

2. The method of claim 1, further comprising:

modifying the first replication policy associated with the first block to obtain a second replication policy, wherein the second replication policy specifies a second replication type.

3. The method of claim 2, further comprising:

receiving a second write operation to write a modified version of the first block to the storage pool;

determining a second replication type for the modified version of first block using the second replication policy associated with the first block;

determining a second number of physical blocks required to write the modified version of the first block to the storage pool using a size of the modified version of the first block and the second replication type; and

writing the modified version of the first block, in accordance with the second replication policy, to the storage pool by filling in the second number of physical blocks.

4. The method of claim 2, further comprising:

receiving a second write operation to write a second block to the storage pool;

determining a second replication type for the second block using the second replication policy, wherein the second block is associated with the second replication policy;

determining a second number of physical blocks required to write the second block to the storage pool using a size of the second block and the second replication type; and

writing the second block, in accordance with the second replication policy, to the storage pool by filling in the second number of physical blocks.

5. The method of claim 2, further comprising:

initiating a background process in response to modifying the first replication policy, wherein the background process is configured to;

obtain the first block from the storage pool, and

re-write the first block to the storage pool using the second replication policy.

6. The method of claim 1, wherein the first replication policy corresponds to one selected from the group consisting of:

a block level replication policy, a file level replication policy, and a file system replication policy.

7. A system for writing data, comprising:

a storage pool comprising;

a plurality of child blocks, wherein each of the plurality of child blocks comprises one selected from the group consisting of a data block and an indirect block, wherein the indirect block references at least one of the plurality of child blocks;

a parent block referencing at least one child block; and

a file system configured to write a first block to the storage pool, wherein the first block is one selected from the group consisting of the parent block and one of the plurality of child blocks,

wherein the file system writes the first block to the storage pool using the following method steps;

determining a first replication type for the first block using a first replication policy associated with the first block;

determining a first number of physical blocks required to write the first block to the storage pool using a size of the first block and the first replication type; and

writing the first block, in accordance with the first replication policy, to the storage pool by filling in the first number of physical blocks.

8. The system of claim 7, wherein the file system is further configured to:

modify the first replication policy associated with the first block to obtain a second replication policy, wherein the second replication policy specifies a second replication type.

9. The system of claim 8, wherein the file system is further configured to:

receive a second write operation to write a modified version of the first block to the storage pool;

determine a second replication type for the modified version of first block using the second replication policy associated with the first block;

determine a second number of physical blocks required to write the modified version of the first block to the storage pool using a size of the modified version of the first block and the second replication type; and

write the modified version of the first block, in accordance with the first replication policy, to the storage pool by filling in the second number of physical blocks.

10. The system of claim 8, wherein the file system is further configured to:

receive a second write operation to write a second block to the storage pool;

determine a second replication type for the second block using the second replication policy, wherein the second block is associated with the second replication policy;

determine a second number of physical blocks required to write the second block to the storage pool using a size of the second block and the second replication type; and

write the second block, in accordance with the second replication policy, to the storage pool by filling in the second number of physical blocks.

11. The system of claim 8, wherein the file system is further configured to:

initiate a background process in response to modifying the first replication policy, wherein the background process is configured to;

obtain the first block from the storage pool, and

re-write the first block to the storage pool using the second replication policy.

12. The system of claim 7, wherein the first replication policy corresponds to one selected from the group consisting of:

a block level replication policy, a file level replication policy, and a file system replication policy.

13. A computer usable medium comprising computer readable program code embodied therein for causing a computer system to:

determine a first replication type for the first block using a first replication policy associated with the first block;

determine a first number of physical blocks required to write the first block to the storage pool using a size of the first block and the first replication type; and

write the first block, in accordance with the first replication policy, to the storage pool by filling in the first number of physical blocks.

14. The computer usable medium of claim 13, further comprising computer readable program code embodied therein for causing the computer system to:

modify the first replication policy associated with the first block to obtain a second replication policy, wherein the second replication policy specifies a second replication type.

15. The computer usable medium of claim 14, further comprising computer readable program code embodied therein for causing the computer system to:

receive a second write operation to write a modified version of the first block to the storage pool;

determine a second replication type for the modified version of first block using the second replication policy associated with the first block;

determine a second number of physical blocks required to write the modified version of the first block to the storage pool using a size of the modified version of the first block and the second replication type; and

write the modified version of the first block, in accordance with the first replication policy, to the storage pool by filling in the second number of physical blocks.

16. The computer usable medium of claim 14, further comprising computer readable program code embodied therein for causing the computer system to:

receive a second write operation to write a second block to the storage pool;

determine a second replication type for the second block using the second replication policy, wherein the second block is associated with the second replication policy;

determine a second number of physical blocks required to write the second block to the storage pool using a size of the second block and the second replication type; and

write the second block, in accordance with the second replication policy, to the storage pool by filling in the second number of physical blocks.

17. The computer usable medium of claim 14, further comprising computer readable program code embodied therein for causing the computer system to:

initiate a background process in response to modifying the first replication policy, wherein the background process is configured to;

obtain the first block from the storage pool, and

re-write the first block to the storage pool using the second replication policy.

18. The computer usable medium of claim 13, wherein the first replication policy corresponds to one selected from the group consisting of:

a block level replication policy, a file level replication policy, and a file system replication policy.