DATA STORAGE BASED ON MEMORY PERSISTENCY

• US 20160170897A1
• Filed: 12/11/2014
• Published: 06/16/2016
• Est. Priority Date: 12/11/2014
• Status: Active Grant

• Current Assignee: Empire Technology Development LLC (Allied Inventors Management, LLC)
• Original Assignee: Empire Technology Development LLC (Allied Inventors Management, LLC)
• Inventors: Solihin, Yan
• Granted Patent: US 9,916,255 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 11/1441 Resetting or repowering
• CPC Class Codes: G06F 11/1446 Point-in-time backing up or restoration of persistent data
• CPC Class Codes: G06F 12/0804 with main memory updating G06F12/0806 takes precedence
• CPC Class Codes: G06F 12/0868 Data transfer between cache memory and other subsystems, e.g. storage devices or host systems
• CPC Class Codes: G06F 12/0871 Allocation or management of cache space
• CPC Class Codes: G06F 12/0897 with two or more cache hierarchy levels with multilevel cache hierarchies G06F12/0811
• CPC Class Codes: G06F 12/1009 using page tables, e.g. page table structures
• CPC Class Codes: G06F 2212/1032 Reliability improvement, data loss prevention, degraded operation etc
• CPC Class Codes: G06F 2212/205 Hybrid memory, e.g. using both volatile and non-volatile memory
• CPC Class Codes: G06F 2212/311 In host system
• CPC Class Codes: G06F 2212/502 using adaptive policy
• CPC Class Codes: G06F 2212/657 Virtual address space management

Abstract

Technologies are generally described for methods and systems effective to store data in a memory module. The memory module may include a volatile portion and a non-volatile portion. The methods may comprise receiving, by a processor, a request to store the data. The request may include an indication of a virtual address. The methods may further include determining, by the processor, a persistency of the data based on the virtual address. The methods may further include performing a first operation of identifying a particular portion of the memory module based on the virtual address. The methods may further include generating a command to store the data in the particular portion of the memory module. The methods may further include controlling the operating system to perform a second operation of updating a translation lookaside buffer to indicate the persistency of the data.

Claims

1. A method to store data in a memory module, where the memory module includes a volatile portion and a non-volatile portion, the method comprising, by a processor:

receiving a request to store the data, where the request includes a virtual address associated with the data;

determining a persistency of the data based on the virtual address;

identifying a particular portion of the memory module based on the virtual address; and

generating a command to store the data in the particular portion of the memory module, wherein the particular portion corresponds to the persistency.

2. The method of claim 1, wherein identifying the particular portion of the memory module includes:

analyzing a page table to determine a physical address in the particular portion of the memory, wherein the virtual address is mapped to the physical address; and

identifying a page frame in the memory module that corresponds to the physical address.

3. The method of claim 1, further comprising, controlling an operating system to perform operations of:

mapping a first set of virtual addresses accessible by the processor, to a first set of physical addresses, wherein the first set of physical addresses is associated with the volatile portion;

mapping a second set of virtual addresses accessible by the processor, to a second set of physical addresses, wherein the second set of physical addresses is associated with the non-volatile portion; and

generating a map to indicate the mapping of the first set of virtual addresses to the first set of physical addresses, and to indicate the mapping of the second set of virtual addresses to the second set of physical addresses.

4. The method of claim 1, further comprising controlling an operating system to perform an operation of updating a page table after generating the command, wherein updating the page table comprises updating a storage location of the data to reflect the persistency of the data.

5. The method of claim 1, wherein the particular portion includes the non-volatile portion, and wherein generating the command includes generating:

a first instruction to store the data in the volatile portion; and

a second instruction to write the data from the volatile portion to the non-volatile portion.

6. The method of claim 1, wherein determining the persistency of the data includes analyzing a translation lookaside buffer.

7. The method of claim 1, wherein generating the command includes generating the command to store the data in a first page frame in the volatile portion, and the method further comprises:

receiving a request to modify the persistency of the data;

controlling an operating system to perform operations of;

allocating a second page frame in the non-volatile portion;

copying the data from the first page frame to the second page frame; and

modifying a persistency attribute of the data in a page table.

8. The method of claim 7, wherein the virtual address is mapped to the first page frame, and the method further comprising controlling the operating system to perform operations of:

prior to allocating the second page frame, locking at least a portion of the page table that corresponds to the virtual address;

prior to modifying the persistency attribute, mapping the virtual address, that corresponds to the locked portion of the page table, to the second page frame; and

subsequent to modifying the persistency attribute, unlocking the locked portion of the page table that corresponds to the virtual address.

9. The method of claim 7, wherein prior to allocating the second page frame, the method further comprises:

identifying a dirty data block in the data; and

after identifying the dirty data block, writing the dirty data block to the non-volatile portion of the memory module.

10. The method of claim 1, wherein generating the command includes generating the command to store the data in a first page frame in the memory module, and the method further comprises:

receiving a request to modify the persistency of the data;

controlling an operating system to perform operations of;

allocating a second page frame in the volatile portion;

copying the data from the first page frame to the second page frame; and

modifying a persistency attribute of the data page in a page table.

11. The method of claim 10, wherein the virtual address is mapped to the first page frame, and the method further comprising controlling the operating system to perform operations of:

prior to allocating the second page frame, locking at least a portion of the page table that corresponds to the virtual address;

prior to modifying the persistency attribute, mapping the virtual address, that corresponds to the locked portion of the page table, to the second page frame; and

subsequent to modifying the persistency attribute, unlocking the locked portion of the page table that corresponds to the virtual address.

12. A device effective to control storage of data in a memory module, where the memory module includes a volatile portion and a non-volatile portion, the device comprising:

a processor that includes;

a first unit effective to;

receive a request to store the data, where the request includes a virtual address associated with the data;

determine a persistency of the data based on the virtual address;

a second unit, coupled to the first unit, effective to identify a particular portion of the memory module based on the virtual address; and

the first unit is further effective to generate a command to store the data in the particular portion of the memory module, wherein the particular portion corresponds to the persistency.

13. The device of claim 12, wherein the second unit is further effective to:

determine an address in the particular portion of the memory, wherein the virtual address is mapped to the determined address in the particular portion of the memory; and

identify a page frame in the memory module based on the determined address.

14. The device of claim 12, wherein the second unit is further effective to control an operating system to:

generate a map to indicate a mapping of a first set of virtual addresses to a first set of physical addresses associated with the volatile portion, and to indicate a mapping of a second set of virtual addresses to a second set of physical addresses associated with the non-volatile portion.

15. The device of claim 12, wherein the second unit is further effective to, in response to the generation of the command, control an operating system to update a storage location of the data to reflect the persistency of the data.

16. The device of claim 12, wherein the particular portion includes the non-volatile portion, and the command is effective to:

store the data in the volatile portion; and

write the data from the volatile portion to the non-volatile portion.

17. The device of claim 12, wherein the determination of the persistency of the data is based on a translation lookaside buffer.

18. The device of claim 12, wherein the command includes a command to store the data in a first page frame in the volatile portion, the first unit is further effective to receive a request to modify the persistency of the data, and the second unit, in response to the receipt of the request to modify the persistency of the data at the first unit, is further effective to control an operating system to:

allocate a second page frame in the non-volatile portion;

copy the data from the first page frame to the second page frame; and

modify a persistency attribute of the data in a page table.

19. The device of claim 18, wherein the virtual address is mapped to the first page frame, and the second unit is further effective to control the operating system to:

modify a protection attribute to lock at least a portion of the page table that corresponds to the virtual address prior to the allocation of the second page frame;

map the virtual address to the second page frame prior to the modification of the persistency attribute; and

modify the protection attribute to unlock the portion of the page table that corresponds to the virtual address subsequent to modification of the persistency attribute.

20. The device of claim 18, wherein prior to allocation of the second page frame, the second unit is further effective to:

identify a dirty data block in the data; and

in response to the identification of the dirty data block, write the dirty data block to the non-volatile portion of the memory module.

21. The device of claim 12, wherein the command is a command to store the data in a first page frame in the memory module, the first unit is further effective to receive a request to modify the persistency of the data, and the second unit, in response to the receipt of the request to modify the persistency of the data at the first unit, is further effective to control an operating system to:

allocate a second page frame in the volatile portion;

copy the data from the first page frame to the second page frame; and

modify a persistency attribute of the data page in the page table.

22. The device of claim 21, wherein the virtual address is mapped to the first page frame, and the second unit is further effective to control the operating system to:

modify a protection attribute of the data to lock at least a portion of the page table that corresponds to the virtual address prior to the allocation of the second page frame;

map the virtual address to the second page frame prior to the modification of the persistency attribute; and

modify the protection attribute of the data to unlock the portion of the page table that corresponds to the virtual address subsequent to the modification of the persistency attribute.

23. A method to modify a persistency of data stored in a memory module, where the memory module includes a volatile portion and a non-volatile portion, the method comprising, by a processor:

receiving a request to modify the persistency of the data, wherein the data is stored in a first page frame of a first portion of the memory module, and the persistency of the data is based on a storage location of the data in the memory module; and

controlling an operating system to perform operations of;

locking at least a portion of a page table that corresponds to the virtual address mapped to the first page frame to activate a write-protected mode of the virtual address;

based on the request, allocating a second page frame of a second portion of the memory module;

copying the data from the first page frame to the second page frame to modify the storage location of the data; and

modifying a persistency attribute of the data in a page table to indicate a modification of the storage location of the data, wherein the modification of the storage location of the data is effective to modify the persistency of the data.

24. The method of claim 23, further comprising, controlling the operating system to perform operations of:

prior to modifying the persistency attribute, mapping the locked portion of the page table that corresponds to the virtual address to the second page frame; and

subsequent to modifying the persistency attribute, unlocking the locked portion of the page table that corresponds to the virtual address to deactivate the write-protected mode of the virtual address.

25. The method of claim 23, wherein the first portion includes the volatile portion of the memory module, and the second portion includes the non-volatile portion of the memory module.

26. The method of claim 25, further comprising prior to allocating the second page frame:

identifying a dirty data block in the data; and

after identifying the dirty data block, writing the dirty data block from the volatile portion to the non-volatile portion of the memory module.

27. The method of claim 23, wherein the first portion includes the non-volatile portion of the memory module, and the second portion includes the volatile portion of the memory module.