Flash memory allocation for improved performance and endurance
View Patent ↗A flash storage device having improved write performance is provided. The device includes a storage block having a plurality of physical pages and a controller configured to allocate subsets of the plurality of physical pages to a plurality of logical addresses, respectively, and to write data to the plurality of physical pages. Each of the subsets of physical pages includes more than one physical page. Upon receiving a first write request for one of the logical addresses, data from the first write request is written to a first physical page of the physical pages allocated to the logical address. Upon receiving a second write request for one of the logical address, the data from the second write request is written to a second physical page allocated to the logical address and the first physical page allocated to the logical address is invalidated.
1. A flash storage device comprising:
a storage block having a plurality of physical pages; and
a controller configured to allocate subsets of the plurality of physical pages to a plurality of logical addresses, respectively, and to write data to the plurality of physical pages,
wherein each of the subsets of the plurality of physical pages comprises more than one physical page.
2. The flash storage device according to claim 1 , wherein all of the allocated subsets of the plurality of physical pages include an identical number of physical pages.
3. The flash storage device according to claim 2 , wherein the number of physical pages is one of 2, 4, 8 and 16.
4. The flash storage device according to claim 1 , wherein the subsets of the plurality of physical pages are allocated to the plurality of logical addresses upon flash initialization of the storage block.
5. The flash storage device according to claim 1 , wherein, in response to a first write request for one of the plurality of logical addresses, the controller is configured to write data from the first write request to a first physical page in the subset of the plurality of physical pages allocated to the one of the plurality of logical addresses, and
in response to a second write request for the one of the plurality of logical addresses, the controller is further configured to write data from the second write request to a second physical page in the subset of the plurality of physical pages allocated to the one of the plurality of logical addresses and invalidate the first physical page in the subset of the plurality of physical pages allocated to the one of the plurality of logical addresses.
6. The flash storage device according to claim 5 , wherein the controller is configured to invalidate the first physical page by setting an invalid flag in a field associated with the first physical page.
7. The flash storage device according to claim 5 , wherein the controller is configured to invalidate the first physical page by setting a pointer value in a field associated with the first physical page, wherein the pointer value identifies an available physical page in the subset of the plurality of physical pages allocated to the one of the plurality of logical addresses.
8. A flash storage device comprising:
a plurality of storage blocks, each storage block having a plurality of physical pages; and
a controller configured to allocate subsets of the plurality of physical pages in each of the plurality of storage blocks to a plurality of logical addresses, respectively, and to write data to the plurality of physical pages,
wherein each of the subsets of the plurality of physical pages comprises more than one physical page.
9. The flash storage device according to claim 8 , all of the allocated subsets of the plurality of physical pages include an identical number of physical pages.
10. The flash storage device according to claim 9 , wherein the number of physical pages is one of 2, 4, 8 and 16.
11. The flash storage device according to claim 8 , wherein each of the allocated subsets of the plurality of physical pages of a first one of the plurality of storage blocks includes a first number of physical pages and each of the allocated subsets of the plurality of physical pages of a second one of the plurality of storage blocks includes a second number of physical pages,
wherein, the first number of physical pages is different than the second number of physical pages.
12. The flash storage device according to claim 8 , wherein the subsets of the plurality of physical pages are allocated to the plurality of logical addresses upon flash initialization of the plurality of storage blocks.
13. The flash storage device according to claim 8 , wherein in response to a first write request for one of the plurality of logical addresses, the controller is configured to write data from the first write request to a first physical page in the subset of the plurality of physical pages allocated to the one of the plurality of logical addresses, and
in response to a second write request for the one of the plurality of logical addresses, the controller is further configured to write data from the second write request to a second physical page in the subset of the plurality of physical pages allocated to the one of the plurality of logical addresses and invalidate the first physical page in the subset of the plurality of physical pages allocated to the one of the plurality of logical addresses.
14. The flash storage device according to claim 13 , wherein the controller is configured to invalidate the first physical page by setting an invalid flag in a field associated with the first physical page.
15. The flash storage device according to claim 13 , wherein the controller is configured to invalidate the first physical page by setting a pointer value in a field associated with the first physical page, wherein the pointer value identifies an available physical page in the subset of the plurality of physical pages allocated to the one of the plurality of logical addresses.
16. A method for managing a flash storage device, the method comprising the steps of:
allocating subsets of a plurality of physical pages in a storage block to a plurality of logical addresses, respectively, wherein each of the subsets of the plurality of physical pages comprises more than one physical page;
receiving a first write request for one of the plurality of logical addresses; and
writing data from the first write request to a first physical page of the plurality of physical pages allocated to the one of the plurality of logical addresses.
17. The method according to claim 16 , further comprising:
receiving a second write request to the one of the plurality of logical addresses;
writing data from the second write request to a second physical page of the plurality of physical pages allocated to the one of the plurality of logical addresses; and
invalidating the first physical page.
18. The method according to claim 17 , wherein invalidating the first physical page comprises setting an invalid flag in a field associated with the first physical page.
19. The method according to claim 17 , wherein invalidating the first physical page comprises setting a pointer value in a field associated with the first physical page, wherein the pointer value identifies an available physical page in the subset of the plurality of physical pages allocated to the one of the plurality of logical addresses.