Dynamic block categorization to improve reliability and performance in memory sub-system
A set of threshold voltage distribution width measurements are obtained for a block in a memory device. An endurance estimate is determined for the block based on the threshold voltage distribution width measurements. The endurance estimate comprises an indication of an estimated number of program/erase cycles during which data can be reliably stored by the block. One or more parameters of the block are managed based on the endurance estimate.
1 . A system comprising:
a memory device comprising a set of blocks; and
a processing device coupled to the memory device, the processing device configured to perform operations comprising:
obtaining a set of threshold voltage distribution width measurements for a block in the set of blocks;
assigning the block to a group among multiple groups of blocks based on the set of threshold voltage distribution width measurements;
determining an endurance estimate for the block based on an endurance category assigned to the group, the determining of the endurance estimate comprising determining an estimated number of program/erase cycles during which the block is able to store data reliably based on the endurance category; and
managing one or more parameters of the block based on the endurance estimate.
2 . The system of claim 1 , wherein the operations comprise:
determining a range of threshold voltage distribution width degradation rates among the set of blocks; and
dividing the range into multiple sub-ranges, where the assigning of the block to the group is based on the threshold voltage distribution width degradation rate for the block corresponding to a sub-range associated with group.
3 . The system of claim 1 , wherein the managing of the one or more parameters of the block comprises maintaining the block in a static single level cell pool for a number of program/erase cycles based on the endurance estimate.
4 . The system of claim 1 , wherein the determining of the endurance estimate for the block comprises accessing look-up table to identify the endurance estimate for the endurance category.
5 . The system of claim 1 , wherein the operations comprise assigning the group to the endurance category, the endurance category being associated with the endurance estimate.
6 . The system of claim 1 , wherein the obtaining of the set of threshold voltage distribution width measurements comprises:
measuring a first threshold voltage distribution width for the block based on a first number of program/erase cycles being performed on the block; and
measuring a second threshold voltage distribution width for the block based on a second number of program/erase cycles being performed on the block.
7 . The system of claim 6 , wherein the measuring of the first threshold voltage distribution width comprises:
determining a top edge and bottom edge of a threshold voltage distribution of the block; and
determining a difference between the top edge and the bottom edge of the threshold voltage distribution.
8 . The system of claim 1 , wherein the managing of the one or more parameters comprises:
assigning a program/erase cycle threshold to the block based on the estimated endurance, the program/erase cycle threshold defining a maximum number of program/erase cycles to be performed on the block;
determining the maximum number of program/erase cycles have been performed on the block; and
based on the determining the maximum number of program/erase cycles have been performed, retiring the block.
9 . The system of claim 1 , wherein the managing of the one or more parameters comprises dynamically adjusting wear-leveling on the block based on the endurance estimate.
10 . A method comprising:
obtaining a set of threshold voltage distribution width measurements for a block in a memory device;
assigning the block to a group among multiple groups of blocks based on the set of threshold voltage distribution width measurements;
determining, by a processing device, an endurance estimate for the block based on an endurance category assigned to the group, the determining of the endurance estimate comprising determining an estimated number of program/erase cycles during which the block is able to store data reliably based on the endurance category; and
managing one or more parameters of the block based on the endurance estimate.
11 . The method of claim 10 , comprising:
determining a range of threshold voltage distribution width degradation rates among the set of blocks; and
dividing the range into multiple sub-ranges, where the assigning of the block to the group is based on the threshold voltage distribution width degradation rate for the block corresponding to a sub-range associated with group.
12 . The method of claim 10 , wherein the managing of the one or more parameters of the block comprises maintaining the block in a static single level cell pool for a number of program/erase cycles based on the endurance estimate.
13 . The method of claim 10 , wherein the determining of the endurance estimate for the block comprises accessing look-up table to identify the endurance estimate for the endurance category.
14 . The method of claim 10 , comprising assigning the group to the endurance category, the endurance category being associated with the endurance estimate.
15 . The method of claim 10 , wherein the obtaining of the set of threshold voltage distribution width measurements comprises:
measuring a first threshold voltage distribution width for the block based on a first number of program/erase cycles being performed on the block; and
measuring a second threshold voltage distribution width for the block based on a second number of program/erase cycles being performed on the block.
16 . The method of claim 15 , wherein the measuring of the first threshold voltage distribution width comprises:
determining a top edge and bottom edge of a threshold voltage distribution of the block; and
determining a difference between the top edge and the bottom edge of the threshold voltage distribution.
17 . The method of claim 10 , wherein the managing of the one or more parameters comprises:
assigning a program/erase cycle threshold to the block based on the estimated endurance, the program/erase cycle threshold defining a maximum number of program/erase cycles to be performed on the block;
determining the maximum number of program/erase cycles have been performed on the block; and
based on the determining the maximum number of program/erase cycles have been performed, retiring the block.
18 . The method of claim 10 , wherein the managing of the one or more parameters comprises dynamically adjusting wear-leveling on the block based on the endurance estimate.
19 . A non-transitory computer-readable storage medium comprising instructions that, when executed by a processing device, configure the processing device to perform operations comprising:
obtaining a set of threshold voltage distribution width measurements for a block in the set of blocks;
assigning the block to a group among multiple groups of blocks based on the set of threshold voltage distribution width measurements;
determining an endurance estimate for the block based on an endurance category assigned to the group, the determining of the endurance estimate comprising determining an estimated number of program/erase cycles during which the block is able to store data reliably based on the endurance category; and
managing one or more parameters of the block based on the endurance estimate.
20 . A non-transitory computer-readable storage medium of claim 19 , wherein operations comprise:
determining a range of threshold voltage distribution width degradation rates among the set of blocks; and
dividing the range into multiple sub-ranges, where the assigning of the block to the group is based on the threshold voltage distribution width degradation rate for the block corresponding to a sub-range associated with group.