Crash consistency

摘要

A method, system, and computer program product comprising using a tracking structure to map a first portion and a second portion of a non-volatile storage medium to a logical representation of the non-volatile storage medium; wherein the first portion is presented by the logical representation as writable storage and using the tracking structure to enable the logical representation to present the data written to the second portion as the data corresponding to the write in the first portion.

主权项

1. A system for data consistency, the system comprising:
a consistency layer; a non-volatile storage medium having a first portion and a second portion; a tracking structure; a memory-mapped file facility; and
computer-executable logic operating in memory, wherein the computer-executable program logic is configured to enable one or more processors to execute: using the tracking structure to map the first portion and the second portion of the non-volatile storage medium to a logical representation of the non-volatile storage medium; wherein the first portion is presented by the logical representation as writable storage; establishing a memory-mapped file enabled to be paged to the non-volatile storage medium; receiving, at the consistency layer, a write IO to the logical representation; wherein the write IO corresponds to a space on the first portion of non-volatile storage medium;
writing the write IO to the second portion of the non-volatile storage medium; marking the tracking structure to denote the space on the second portion as corresponding to the data corresponding to the space on the first portion of the non-volatile storage medium to which the write IO is directed; and using the tracking structure to enable the logical representation to present the data written to the second portion as the data corresponding to the write in the first portion.