Memory system storing management information and method of controlling same

摘要

A memory system includes a management-information restoring unit. The management-information restoring unit determines whether a short break has occurred referring to a pre-log or a post-log in a NAND memory. The management-information restoring unit determines that a short break has occurred when the pre-log or the post-log is present in the NAND memory. In that case, the management-information restoring unit determines timing of occurrence of the short break, and, after selecting a pre-log or a post-log used for restoration, performs restoration of the management information reflecting these logs on a snapshot. Thereafter, the management-information restoring unit applies recovery processing to all write-once blocks in the NAND memory, takes the snapshot again, and opens the snapshot and the logs in the past.

主权项

1. A memory system storing management information comprising:
a nonvolatile memory; a volatile memory configured to store at least one part of first management information stored in the nonvolatile memory; and a memory controller configured to perform data management in the nonvolatile memory based on the first management information stored in the volatile memory, wherein the memory controller includes: a management-information storing unit configured to store a log indicating difference information before and after updating the first management information in the nonvolatile memory, the log including a first log being created before updating the first management information and a second log being created after updating the first management information, and to store the first management information in the nonvolatile memory as second management information; and a management-information storing unit configured to store the first management information on the volatile memory based on at least one of the second management information and the log stored in the nonvolatile memory, wherein when an error has occurred in the memory system, the management-information storing unit is configured to store the first management information as third management information in the nonvolatile memory.