Handling unclean shutdowns for a system having non-volatile memory

摘要

Systems and methods are disclosed for handling unclean shutdowns for a system having non-volatile memory (“NVM”). In some embodiments, the system can leverage from information obtained from index pages in order to efficiently reconstruct logical-to-physical mappings after an unclean shutdown event. In other embodiments, the system can reconstruct logical-to-physical mappings by leveraging from context information stored in a NVM. In further embodiments, context information can be used in conjunction with index pages to reconstruct logical-to-physical mappings after an unclean shutdown.

主权项

1. A method for recovering from a device failure, the method comprising:
detecting that an unclean shutdown event has occurred; scanning a plurality of index pages of a non-volatile memory (“NVM”) for ages of the plurality of index pages, said plurality of index pages being stored in said NVM, and wherein the scanning the plurality of index pages potentially avoids scanning every data block of the NVM; comparing the ages of the plurality of index pages with ages of data pages of the NVM corresponding to the plurality of index pages; determining the reliability of each index page of the plurality of index pages based at least in part on the comparison; and selectively using an index page to reconstruct a logical to physical mapping based on the determined reliability of that index page.