US 11,899,633 B2
Managing storage device scrubbing
Bing Liu, Tianjin (CN); and Rahul Deo Vishwakarma, Bangalore (IN)
Assigned to EMC IP Holding Company LLC, Hopkinton, MA (US)
Filed by EMC IP Holding Company LLC, Hopkinton, MA (US)
Filed on Jul. 14, 2020, as Appl. No. 16/928,155.
Prior Publication US 2022/0019564 A1, Jan. 20, 2022
Int. Cl. G06F 16/215 (2019.01); G06F 9/48 (2006.01)
CPC G06F 16/215 (2019.01) [G06F 9/4881 (2013.01)] 17 Claims
OG exemplary drawing
 
1. For a storage system including a plurality PSDs (physical storage devices), a method comprising:
selecting, using a processor, an eligible set of two or more of the plurality of PSDs that are eligible for scrubbing, wherein said selecting the eligible set includes using a processor to select each PSD of the eligible set based on a similarity between characteristics of said each PSD and characteristics of PSDs previously determined to be eligible for scrubbing;
responsive to said selecting, storing, in a memory using a processor, the eligible set of the two or more PSDs eligible for scrubbing;
receiving, using a processor, a health score set of health scores for the two or more PSDs in the eligible set, wherein the health score set identifies, for each PSD in the eligible set, a corresponding health score in the health score set;
receiving, using a processor and in accordance with the health score set, a relative eligibility for each PSD of the eligible set relative to other PSDs of the eligible set;
receiving, using a processor, a table defining PSD health categories with associated health score ranges and associated scrub frequency categories, wherein each PSD health category is associated with a corresponding one of the associated health score ranges and is associated with a corresponding one of the associated scrub frequency categories;
for each PSD of the eligible set, mapping, using a processor, said each PSD to one of the PSD health categories and one of the scrub frequency categories associated with said one PSD health category, wherein said mapping is performed in accordance with the health score set and in accordance with the table, wherein a first of the PSD health categories is associated with a first of the scrub frequency categories and a second of the PSD health categories is associated with a second of the scrub frequency categories, wherein the first PSD health category denotes a healthier PSD state than the second PSD health category, and wherein the second scrub frequency denotes a higher scrub frequency than the first scrub frequency, wherein a first PSD of the eligible set has a first health score of the health score set which is mapped by said mapping to the first PSD health category, wherein a second PSD of the eligible set has a second health score of the health score set which is mapped by said mapping to the second PSD health category, and wherein the first PSD is healthier than the second PSD as indicated by the first health score of the first PSD being greater than the second health score of the second PSD;
scheduling, using a processor and in accordance with a schedule, scrubbing of the eligible set of PSDs, including, for each PSD of the eligible set, scheduling a scrubbing of said each PSD based on the relative eligibility of said each PSD and based on a particular one of the scrub frequency categories mapped to said each PSD by said mapping, wherein the schedule indicates to scrub the second PSD, which is less healthy than the first PSD, more frequently than said first PSD; and
scrubbing, using a processor, the eligible set of PSDs according to the schedule, wherein said scrubbing scrubs the second PSD, which is less healthy than the first PSD, more frequently than said first PSD, and wherein said scrubbing includes detecting a media error and corrupted data, and reconstructing the corrupted data into a corresponding proper form.