COMBINING VIRTUAL MAPPING METADATA AND PHYSICAL SPACE MAPPING METADATA

• US 20150227468A1
• Filed: 02/11/2014
• Published: 08/13/2015
• Est. Priority Date: 02/11/2014
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: SASSON, Ben, SHALEV, Ori, BERGER, Yuval, SHASTKY, Yosef
• Granted Patent: US 9,329,780 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 12/10 Address translation
• CPC Class Codes: G06F 16/00 Information retrieval; Database structures therefor; File system structures therefor
• CPC Class Codes: G06F 3/06 Digital input from, or digital output to, record carriers , e.g. RAID, emulated record carriers or networked record carriers
• CPC Class Codes: G06F 3/0604 Improving or facilitating administration, e.g. storage management
• CPC Class Codes: G06F 3/061 Improving I/O performance
• CPC Class Codes: G06F 3/0626 Reducing size or complexity of storage systems
• CPC Class Codes: G06F 3/0647 Migration mechanisms
• CPC Class Codes: G06F 3/0665 at area level, e.g. provisioning of virtual or logical volumes
• CPC Class Codes: G06F 3/067 Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS]
• CPC Class Codes: G06F 3/0683 Plurality of storage devices
• CPC Class Codes: G06F 3/0689 Disk arrays, e.g. RAID, JBOD

Abstract

For combining virtual mapping metadata and physical space mapping metadata in a storage system by a processor device in a computing environment, data and metadata are maintained into separate virtual streams. The separate virtual streams include a metadata stream for the metadata and a data stream for the data. Information of a mapping of logical data to a location on the data stream and a current state of unused spaces in the data stream is linearly distributed within the metadata stream.

Claims

1. A method for combining virtual mapping metadata and physical space mapping metadata in a storage system by a processor device in a computing environment, the method comprising:

maintaining data and metadata into separate virtual streams, wherein the separate virtual streams include a metadata stream for the metadata and a data stream for the data; and

linearly distributing within the metadata stream information of a mapping of logical data to a location on the data stream and a current state of unused spaces in the data stream.

2. The method of claim 1, further including arranging the metadata stream in a fixed logical relationship with the data and storing the metadata having data mapping in fixed spaces together with physical unused space mapping.

3. The method of claim 1, further including deducing by a linear function a location of metadata related to an input/output (I/O) operation required for acting on regions of logical data and regions of unused spaces in the data stream.

4. The method of claim 1, further including storing unused-space metadata by linearly organizing the unused-space metadata of the data stream in the metadata stream.

5. The method of claim 1, further including mapping the unused-space of the data stream using a bit-mask that is linearly stored to the data stream inside the metadata stream.

6. The method of claim 1, further including performing at least one of:

determining the metadata for each input/output (I/O) operation received using a linear function operation, wherein the function operation is an offset of the metadata in the metadata stream that is equal to the I/O operation multiplied by a maximal metadata ratio,

allocating the metadata on the metadata stream and dividing the metadata stream into fixed size block that is responsible for describing a size of a logical space, wherein the logical space is equal to one divided by the maximal metadata ratio, and

determining if the metadata has been previously loaded.

7. The method of claim 1, further including performing at least one of:

using a bit-mask to locate a preferred unused-space of the data stream when space in the data stream is required for a write operation,

automatically storing logically related data in adjacent locations in the data stream, and

allocating space from a physical target of a currently active metadata block.

8. The method of claim 1, further including calculating an offset in the metadata stream associated by multiplying an input/output (I/O) logical offset by a maximal metadata ratio.

9. A system for combining virtual mapping metadata and physical space mapping metadata in a computing storage environment, comprising:

at least one processor device, operable in the computing storage environment, wherein the at least one processor device;

maintains data and metadata into separate virtual streams, wherein the separate virtual streams include a metadata stream for the metadata and a data stream for the data, and

linearly distributes within the metadata stream information of a mapping of logical data to a location on the data stream and a current state of unused spaces in the data stream.

10. The system of claim 9, wherein the at least one processor device arranges the metadata stream in a fixed logical relationship with the data and storing the metadata having data mapping in fixed spaces together with physical unused space mapping.

11. The system of claim 9, wherein the at least one processor device deduces by a linear function a location of metadata related to an input/output (I/O) operation required for acting on regions of logical data and regions of unused spaces in the data stream.

12. The system of claim 9, wherein the at least one processor device stores unused-space metadata by linearly organizing the unused-space metadata over the data stream.

13. The system of claim 9, wherein the at least one processor device maps the unused-space of the data stream using a bit-mask that is linearly stored to the data stream inside the metadata stream.

14. The system of claim 9, wherein the at least one processor device performs at least one of:

determining the metadata for each input/output (I/O) operation received using a linear function operation, wherein the function operation is an offset of the metadata in the metadata stream that is equal to the I/O operation multiplied by a maximal metadata ratio,

allocating the metadata on the metadata stream and dividing the metadata stream into fixed size block that is responsible for describing a size of a logical space, wherein the logical space is equal to one divided by the maximal metadata ratio,

determining if the metadata has been previously loaded,

using a bit-mask to locate a preferred unused-space of the data stream when space in the data stream is required for a write operation,

automatically storing logically related data in adjacent locations in the data stream, and

allocating space from a physical target of a currently active metadata block.

15. The system of claim 9, wherein the at least one processor device calculates an offset in the metadata stream associated by multiplying an input/output (I/O) logical offset by a maximal metadata ratio.

16. A computer program product for combining virtual mapping metadata and physical space mapping metadata in a storage system by a processor device, the computer program product comprising a non-transitory computer-readable storage medium having computer-readable program code portions stored therein, the computer-readable program code portions comprising:

a first executable portion that maintains data and metadata into separate virtual streams, wherein the separate virtual streams include a metadata stream for the metadata and a data stream for the data; and

a second executable portion that linearly distributing within the metadata stream information of a mapping of logical data to a location on the data stream and a current state of unused spaces in the data stream.

17. The computer program product of claim 16, further including a third executable portion that arranges the metadata stream in a fixed logical relationship with the data and storing the metadata having data mapping in fixed spaces together with physical unused space mapping.

18. The computer program product of claim 16, further including a third executable portion that deduces by a linear function a location of metadata related to an input/output (I/O) operation required for acting on regions of logical data and regions of unused spaces in the data stream.

19. The computer program product of claim 16, further including a third executable portion that performs at least one of:

storing unused-space metadata by linearly organizing the unused-space metadata over the data stream,

mapping the unused-space of the data stream using a bit-mask that is linearly stored to the data stream inside the metadata stream,

determining the metadata for each input/output (I/O) operation received using a linear function operation, wherein the function operation is an offset of the metadata in the metadata stream that is equal to the I/O operation multiplied by a maximal metadata ratio,

allocating the metadata on the metadata stream and dividing the metadata stream into fixed size block that is responsible for describing a size of a logical space, wherein the logical space is equal to one divided by the maximal metadata ratio,

determining if the metadata has been previously loaded,

using a bit-mask to locate a preferred unused-space of the data stream when space in the data stream is required for a write operation,

automatically storing logically related data in adjacent locations in the data stream, and

allocating space from a physical target of a currently active metadata block.

20. The computer program product of claim 16, further including a third executable portion that calculates an offset in the metadata stream associated by multiplying an input/output (I/O) logical offset by a maximal metadata ratio.