Compressed block map of densely-populated data structures

Patent metadata

Field	Value
Publication number	US-9582198-B2
Application number	US-201314032121-A
Country	US
Kind code	B2
Filing date	Sep 19, 2013
Priority date	Aug 26, 2013
Publication date	Feb 28, 2017
Grant date	Feb 28, 2017

Abstract

Embodiments of the disclosure provide techniques for creating a compressed mapping structure in a system of resources. For example, a distributed resources system may use delta encoding to store, in memory, numerous entries of dense data structures in the system. In a compressed block of such entries, the distributed resources system encodes the key of each entry as the delta from the key of the previous entry. The content of each entry is encoded similarly. The distributed resources system suppresses the leading zero bits of each resulting field.

First claim

I claim:

1. A method for storing key-value entries of a block map in a host computer system of a system of resources, the method comprising:
given a current entry having a current key having one or more fields and a current payload and a previous entry having a previous key and a previous payload, encoding each of the one or more fields in the current key as a first delta from a corresponding field in the previous key and encoding the current payload as a second delta from the previous payload;
removing leading zero bits in each resulting encoded field of the current key and leading zero bits in the encoded current payload; and
inserting the encoded one or more fields of the current key and the encoded current payload into a datastore residing in memory of the host computer system,
wherein the previous entry and the current entry are successive entries of the block map.

2. The method of claim 1 , wherein the one or more fields corresponds to an object identifier, an offset, and a length, and wherein the current payload corresponds to block addresses of a solid state drive.

3. The method of claim 1 , wherein the system of resources provides a software-defined virtual storage area network.

4. The method of claim 1 , wherein the datastore maintains a cache of recently referenced entries.

5. The method of claim 1 , wherein the current entry is addressed with an index block.

6. The method of claim 1 , wherein the datastore is a logical block addressing table.

7. A non-transitory computer-readable storage medium storing instructions, which, when executed on a processor, performs an operation for storing key-value entries of a block map in a host computer system of a system of resources, the operation comprising:
given a current entry having a current key having one or more fields and a current payload and a previous entry having a previous key and a previous payload, encoding each of the one or more fields in the current key as a first delta from a corresponding field in the previous key and encoding the current payload as a second delta from the previous payload;
removing leading zero bits in each resulting encoded field of the current key and leading zero bits in the encoded current payload; and
inserting the encoded one or more fields of the current key and the encoded current payload into a datastore residing in memory of the host computer system,
wherein the previous entry and the current entry are successive entries of the block map.

8. The computer-readable storage medium of claim 7 , wherein the one or more fields corresponds to an object identifier, an offset, and a length, and wherein the current payload corresponds to block addresses of a solid state drive.

9. The computer-readable storage medium of claim 7 , wherein the system of resources provides a software-defined virtual storage area network.

10. The computer-readable storage medium of claim 7 , wherein the datastore maintains a cache of recently referenced entries.

11. The computer-readable storage medium of claim 7 , wherein the current entry is addressed with an index block.

12. The computer-readable storage medium of claim 7 , wherein the datastore is a logical block addressing table.

13. A system, comprising:
a processor and
a memory hosting a module, which, when executed on the processor, performs an operation for storing key-value entries of a block map in a host computer system of a system of resources, the operation comprising:
given a current entry having a current key having one or more fields and a current payload and a previous entry having a previous key and a previous payload, encoding each of the one or more fields in the current key as a first delta from a corresponding field in the previous key and encoding the current payload as a second delta from the previous payload;
removing leading zero bits in each resulting encoded field of the current key and leading zero bits in the encoded current payload; and
inserting the encoded one or more fields of the current key and the encoded current payload into a datastore residing in memory of the host computer system,
wherein the previous entry and the current entry are successive entries of the block map.

14. The system of claim 13 , wherein the one or more fields corresponds to an object identifier, an offset, and a length, and wherein the current payload corresponds to block addresses of a solid state drive.

15. The system of claim 13 , wherein the system of resources provides a software-defined virtual storage area network.

16. The system of claim 13 , wherein the datastore maintains a cache of recently referenced entries.

17. The system of claim 13 , wherein the current entry is addressed with an index block.

Assignees

• Vmware Inc

Inventors

• Earl William

Classifications

• G06F3/064

  Management of blocks · CPC title

• G06F3/067

  Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS] · CPC title

• G06F3/0613 Primary

  in relation to throughput · CPC title

• G06F3/0667

  at data level, e.g. file, record or object virtualisation · CPC title

• G06F3/0688

  Non-volatile semiconductor memory arrays · CPC title