Memory sub-system with background scan and histogram statistics
View Patent ↗Several embodiments of systems incorporating memory sub-systems are disclosed herein. In one embodiment, a memory sub-system can include a memory component and a processing device configured to perform a background scan on a memory region of the memory component. In some embodiments, the background scan includes generating a bit error count (BEC) of a codeword saved on the memory region and saving statistical information corresponding to the BEC of the codeword to a histogram statistics log. In some embodiments, when the BEC of the codeword is greater than a BEC threshold, a refresh operation is scheduled for the memory region and/or logged. In these and other embodiments, when one or more error recovery error correction code (ECC) operations do not correct bit errors in the codeword, a refresh and/or retirement operation is schedule for the memory region and/or is logged.
1. A system, comprising:
a memory component comprising a plurality of memory regions configured to store a plurality of codewords; and
a processing device operably connected to the memory component, wherein the processing device is configured to
generate a bit error count (BEC) of a first codeword of the plurality of codewords saved to a first memory region in the plurality of memory regions; and
store statistical information corresponding to the BEC of the first codeword in a BEC histogram corresponding to the plurality of codewords, wherein storing the statistical information comprises incrementing a counter value of a bin of the BEC histogram corresponding to the BEC of the first codeword.
2. The system of claim 1 further comprising an error correction code (ECC) engine, and wherein the BEC of the first codeword is less than or equal to a BEC capability of the ECC engine.
3. The system of claim 1 , wherein the first memory region is a memory block, a memory die, a memory page, a stripe of memory pages, or a superblock.
4. The system of claim 3 , wherein the first memory region is a stripe of memory pages, and wherein the processing device is configured to select the first memory region from within an oldest, fully-programmed superblock in the memory component.
5. The system of claim 1 , wherein the processing device is further configured to
determine if one or more bit errors are present in the first codeword; and
perform a limited subset of error recovery error correction code (ECC) operations available to the processing device on the first codeword in an event bit error(s) are present in the first codeword.
6. The system of claim 1 , wherein the processing device is configured to generate the BEC of the first codeword and to store the statistical information corresponding to the BEC of the first codeword in response to a determination that the system is idle.
7. The system of claim 1 , wherein the processing device is configured to generate the BEC of the first codeword and to store the statistical information corresponding to the BEC of the first codeword in response to a determination that a predetermined delay has elapsed since a previous operation to store statistical information in the BEC histogram was completed.
8. The system of claim 1 , wherein the processing device is configured to generate the BEC of the first codeword and to store the statistical information corresponding to the BEC of the first codeword in response to a corresponding command received from a coupled host device.
9. The system of claim 1 , wherein to generate the BEC of the first codeword, the processing device is configured to decode the first codeword of the plurality of codewords saved to the first memory region in the plurality of memory regions.
10. The system of claim 1 , wherein the processing device is further configured to reset the BEC histogram in response to receiving a vender specific command in response to determining that a counter value stored in the BEC histogram reaches a maximum value, and/or after detecting a dynamic program target (DPT) update.
11. A method, comprising:
generating a bit error count (BEC) of a first codeword in a plurality of codewords saved to a first memory region in a plurality of memory regions; and
storing statistical information corresponding to the BEC of the first codeword in a BEC histogram corresponding to the plurality of codewords, wherein storing the statistical information comprises incrementing a counter value of a bin of the BEC histogram corresponding to the BEC of the first codeword.
12. The method of claim 11 further comprising
determining if one or more bit errors are present in the codeword; and
performing a limited subset of available error recovery error correction code (ECC) operations on the first codeword in an event bit error(s) are present in the first codeword.
13. The method of claim 11 further comprising
generating a BEC of a second codeword in the plurality of codewords saved to the first memory region or a second memory region in the plurality of memory regions; and
storing statistical information corresponding to the BEC of the second codeword in the BEC histogram.
14. The method of claim 13 , wherein generating the BEC of the second codeword includes generating the BEC of the second codeword a first time period after generating the BEC of the first codeword in accordance with a scheduled cadence.
15. A non-transitory computer-readable storage medium comprising instructions that, when executed by a processing device, cause the processing device to:
generate a bit error count (BEC) of a first codeword in a plurality of codewords saved to a first memory region in a plurality of memory regions; and
store statistical information corresponding to the BEC of the first codeword in a BEC histogram corresponding to the plurality of codewords, wherein storing the statistical information comprises incrementing a counter value of a bin of the BEC histogram corresponding to the BEC of the first codeword.
16. The non-transitory computer-readable storage medium of claim 15 , wherein the processing device is further to:
determine if one or more bit errors are present in the codeword; and
perform a limited subset of available error recovery error correction code (ECC) operations on the first codeword in an event bit error(s) are present in the first codeword.
17. The non-transitory computer-readable storage medium of claim 15 , wherein the processing device is further to:
generate a BEC of a second codeword in the plurality of codewords saved to the first memory region or a second memory region in the plurality of memory regions; and
store statistical information corresponding to the BEC of the second codeword in the BEC histogram.