Method and device for storage management

Patent metadata

Field	Value
Publication number	US-10657066-B2
Application number	US-201815954812-A
Country	US
Kind code	B2
Filing date	Apr 17, 2018
Priority date	Apr 17, 2017
Publication date	May 19, 2020
Grant date	May 19, 2020

Abstract

Embodiments of the present disclosure provide a method and an apparatus for storage management. For example, there is provided a method comprising: creating a plurality of profiles for address mapping, the profiles comprising a part of mapping relation in the total mapping table and creating an index for a part of the plurality of profiles to accelerate the lookup speed. A corresponding device and computer program product are also disclosed.

First claim

We claim:

1. A method of storage management, comprising:
creating a plurality of profiles for address mapping, a profile containing a part of an address mapping table stored on a non-volatile storage device, and the profile indicating:
a logical starting address of an initial logical block of a plurality of logical blocks,
a physical starting address corresponding to the logical starting address,
the number of the plurality of logical blocks, and
a modification flag bit indicating whether the profile is changed with respect to the address mapping table;

storing the plurality of profiles in a cache in an order of the corresponding logical starting addresses;
creating an index for a part of the plurality of profiles in the cache;
creating a first record for a first physical extent, the first record indicating a physical starting address of the first physical extent and a first number of physical blocks contained therein, at least a part of the plurality of logical blocks indicated by a first profile of the plurality of profiles being mapped to the first physical extent;
creating a second record for a second physical extent, the second record indicating a physical starting address of the second physical extent and a second number of physical blocks contained therein, at least a part of the plurality of logical blocks indicated by a second profile of the plurality of profiles being mapped to the second physical extent;
in response to a physical end address of the first physical extent and a physical starting address of the second physical extent being continuous, merging the first record and the second record to generate a third record, the third record indicating the physical starting address of the first physical extent and a sum of the first number and the second number; and
storing the third record in the cache.

2. The method of claim 1 , wherein creating an index for a part of the plurality of profiles in the cache comprises:
selecting the part of profiles randomly to create the index.

3. The method of claim 1 , wherein creating an index for a part of the plurality of profiles in the cache comprises:
selecting, based on an access frequency, the part of profiles to create the index.

4. The method of claim 1 , further comprising:
in response to the physical end address of the first physical extent and the physical starting address of the second physical extent being non-continuous, storing the first record and the second record in the cache.

5. The method of claim 1 , further comprising:
receiving a request for a target profile, the request indicating an index associated with the target profile; and
searching the target profile in the cache based on the index.

6. The method of claim 5 , further comprising:
in response to the target profile being absent in the cache, creating the target profile based on the address mapping table.

7. The method of claim 5 wherein the request comprises a request to modify a part of the address mapping table contained in the target profile, the method further comprising:
in response to the target profile being present in the cache, updating the part of the address mapping table contained in the target profile.

8. The method of claim 1 , further comprising:
in response to the number of idle profiles in the cache being lower than a first threshold, triggering reclaiming of the plurality of profiles; and
in response to the number of idle profiles in the cache being greater than a second threshold, ceasing the reclaiming.

9. The method of claim 8 , wherein triggering reclaiming of the plurality of profiles comprises:
reclaiming, among the plurality of profiles, profiles not having been changed with respect to the address mapping table.

10. The method of claim 8 , wherein triggering reclaiming of the plurality of profiles comprises:
reclaiming, among the plurality of profiles, profiles having been changed with respect to the address mapping table, comprising:
storing, in the non-volatile storage device, changed address mapping in the changed profiles.

11. The method of claim 8 , further comprising:
removing an index of a reclaimed profile.

12. An electronic device, comprising:
a processor; and
a memory coupled to the processor, the memory having instructions stored therein which, when executed by the processor, cause the electronic device to perform acts comprising:
creating a plurality of profiles for address mapping, one profile containing a part of an address mapping table stored on a non-volatile storage device and the profile indicating:
a logical starting address of an initial logical block of a plurality of logical blocks,
a physical starting address corresponding to the logical starting address,
the number of the plurality of logical blocks, and
a modification flag bit indicating whether the profile is changed with respect to the address mapping table;

storing the plurality of profiles in a cache in an order of the corresponding logical starting addresses;
creating an index for a part of the plurality of profiles in the cache,
creating a first record for a first physical extent, the first record indicating a physical starting address of the first physical extent and a first number of physical blocks contained therein, at least a part of the plurality of logical blocks indicated by a first profile of the plurality of profiles being mapped to the first physical extent:
creating a second record for a second physical extent, the second record indicating a physical starting address of the second physical extent and a second number of physical blocks contained therein, at least a part of the plurality of logical blocks indicated by a second profile of the plurality of profiles being mapped to the second physical extent;
in response to a physical end address of the first physical extent and a physical starting address of the second physical extent being continuous, merging the first record and the second record to generate a third record, the third record indicating the physical starting address of the first physical extent and a sum of the first number and the second number; and
storing the third record in the cache.

13. The device of claim 12 , wherein creating an index for a part of the plurality of profiles in the cache comprises:
selecting the part of profiles randomly to create the index.

14. The device of claim 12 , wherein creating an index for a part of the plurality of profiles in the cache comprises:
selecting, based on an access frequency, the part of profiles to create the index.

15. The device of claim 12 , wherein the acts further comprise:
in response to the physical end address of the first physical extent and the physical starting address of the second physical extent being non-continuous, storing the first record and the second record in the cache.

16. The device of claim 12 , wherein the acts further comprise:
receiving a request for a target profile, the request indicating an index associated with the target profile;
searching the target profile in the cache based on the index.

17. The device of claim 16 , wherein the acts further comprise:
in response to the target profile being absent in the cache, creating the target profile based on the address mapping table.

18. The device of claim 16 , wherein the request comprises a request to modify a part of the address mapping table contained in the target profile, the acts further comprising:
in response to the target profile being present in the cache, updating the part of the address mappi

Assignees

• Emc Ip Holding Co Llc

Inventors

• Han Geng
• Gao Jian
• Li Wayne Weihua
• Kang Jamin
• Dong Jibing

Classifications

• G06F12/1009 Primary

  using page tables, e.g. page table structures · CPC title

• G06F2212/1008

  Correctness of operation, e.g. memory ordering · CPC title

• G06F2212/7203

  Temporary buffering, e.g. using volatile buffer or dedicated buffer blocks · CPC title

• G06F3/0638

  Organizing or formatting or addressing of data · CPC title

• G06F2212/1016

  Performance improvement · CPC title