US 9,811,462 B2
Memory system executing garbage collection
Shinichi Kanno, Tokyo (JP)
Assigned to Toshiba Memory Corporation, Tokyo (JP)
Filed by Toshiba Memory Corporation, Minato-ku, Tokyo (JP)
Filed on Sep. 9, 2015, as Appl. No. 14/848,844.
Claims priority of provisional application 62/155,249, filed on Apr. 30, 2015.
Prior Publication US 2016/0321171 A1, Nov. 3, 2016
Int. Cl. G06F 12/02 (2006.01); G06F 3/06 (2006.01)
CPC G06F 12/0253 (2013.01) [G06F 3/0619 (2013.01); G06F 3/0655 (2013.01); G06F 3/0688 (2013.01); G06F 12/0246 (2013.01); G06F 2212/1016 (2013.01); G06F 2212/7201 (2013.01); G06F 2212/7205 (2013.01)] 7 Claims
OG exemplary drawing
 
1. A memory system comprising:
a nonvolatile memory including first and second memory areas; and
a controller controlling the nonvolatile memory, the controller configured to:
detect data amounts of valid data written to the first memory area and data amounts of valid data written to the second memory area;
update, if writing for the second memory area is executed after writing for the first memory area, at least one of first and second thresholds such that the first threshold corresponding to the first memory area is greater than the second threshold corresponding to the second memory area;
select the first memory area as a memory area of a garbage collection target if the data amounts of the first memory area are smaller than the first threshold, and select the second memory area as the memory area of the garbage collection target if the data amounts of the second memory area are smaller than the second threshold; and
execute garbage collection on the selected memory area of the garbage collection target.