Management method for nonvolatile memory system following power-off
AssigneeSamsung Electronics Co., Ltd.
InventorsChaesuk Lim, Jinhyuk Kim, Taekkyun Lee, Wonchuri Zoo
Life of this patent
Estimating the term…
Abstract
A management method for a memory system executes a first memory system management sequence upon determining that the memory system was normally powered off, and a second sequence upon determining that the memory system was abnormally powered off. The first sequence allows immediate execution of a program operation at a valid data page location extracted from stored metadata, while the second sequence allows execution of a program operation only after programming dummy data to at least one erroneous page.
Claims17
A management method for a memory system including a host and a nonvolatile memory, the management method comprising:
- determining whether the nonvolatile memory was normally or abnormally powered off in response to at least one of a command provided by the host to the nonvolatile memory and power-off data stored in the nonvolatile memory;
- only upon determining that the nonvolatile memory was abnormally powered off, searching for at least one erroneous page among pages of the nonvolatile memory by referencing metadata last stored in the nonvolatile memory before the abnormal power-off, wherein the metadata comprises a valid data page location;
- programming dummy data in the at least one erroneous pages before performing a normal program operation directed to the nonvolatile memory;
- and
- upon determining that the nonvolatile memory was normally powered off, extracting the valid data page location from the metadata, and erasing the power-off data stored in the nonvolatile memory before performing the normal program operation directed to the nonvolatile memory.
A management method for a memory system including a host and a nonvolatile memory, the management method comprising:
- upon rebooting the nonvolatile memory, executing a first management sequence upon determining that the nonvolatile memory was normally powered off, else executing a second management sequence different from the first management sequence upon determining that the nonvolatile memory was abnormally powered off,
- wherein the first management sequence includes execution of a program operation at a valid data page location extracted from metadata stored in the nonvolatile memory and including a valid data page location and erasing of power-off data stored in the nonvolatile memory before performing the program operation, and
- wherein the second management sequence includes execution of the program operation only after searching for at least one erroneous page among pages of the nonvolatile memory by referencing the metadata and programming dummy data to the at least one erroneous page.
A memory device, comprising:
- a memory controller;
- and
- a nonvolatile memory comprising nonvolatile semiconductor memory cells divided into a plurality of N blocks, each block being respectively divided into a plurality of K pages, wherein less than N of the plurality of N blocks is used to store power-off data and location data identifying a location of metadata stored in the nonvolatile memory,
- wherein the memory controller configured to:
- determine whether the nonvolatile memory was normally or abnormally powered off in response to at least one of a command received from a host and the stored power-off data;
- search for at least one erroneous page among the plurality of K pages of the plurality of N blocks of the nonvolatile memory by referencing the metadata, last stored before an abnormal power-off, only upon determining that the nonvolatile memory was abnormally powered off;
- and
- control the nonvolatile memory to program dummy data in the at least one erroneous page before performing a normal program operation directed to the nonvolatile memory, wherein the dummy data is data last programmed during a program operation immediately preceding the abnormal power-off.
Dependencies are inferred from the claim text.