US 11,726,683 B2
Storage system and operating method for moving data between storage devices thereof
Kyung Soo Lee, Gyeonggi-do (KR)
Assigned to SK hynix Inc., Gyeonggi-do (KR)
Filed by SK hynix Inc., Gyeonggi-do (KR)
Filed on May 5, 2021, as Appl. No. 17/308,253.
Claims priority of application No. 10-2020-0144641 (KR), filed on Nov. 2, 2020.
Prior Publication US 2022/0137840 A1, May 5, 2022
Int. Cl. G06F 3/06 (2006.01)
CPC G06F 3/0631 (2013.01) [G06F 3/0604 (2013.01); G06F 3/0647 (2013.01); G06F 3/0652 (2013.01); G06F 3/0683 (2013.01)] 19 Claims
OG exemplary drawing
 
1. A storage system comprising:
a first storage device;
a second storage device;
a cache tier including a first zone group and a second zone group configured to temporarily store data, respectively; and
a system controller configured to move data stored in the first storage device to the cache tier and move the data moved to the cache tier to the second storage device,
wherein the first zone group is allocated to the first storage device,
wherein the second zone group is allocated to the second storage device,
wherein each of the first zone group and the second zone group includes a plurality of data zones configured to store data based on a number of times the data is accessed, and includes a hot data zone, a warm data zone, and a cold data zone,
wherein the system controller is configured to:
load the data stored in the first storage device in a source data zone included in the first zone group, and
move the data loaded in the source data zone to a target data zone included in the second zone group, based on a first access count and a second access count,
wherein the first access count corresponds to a number of access times of the source data zone and the second access count corresponds to a number of access times of a reference data zone included in the second zone group,
wherein the target data zone is determined among the hot data zone, the warm data zone, and the cold data zone based on a comparison result of the first access count and the second access count,
wherein an average value of access counts of data stored in the target data zone is greater than an average value of access counts of data stored in the reference data zone when the first access count is greater than the second access count.