MEMORY ALLOCATION AND RECOVERY STRATEGIES FOR BYTE-ADDRESSABLE NON-VOLATILE RAM (NVRAM)

摘要

Disclosed herein are innovations in memory management and data recovery for systems that operate using storage class memory (SCM), such as non-volatile RAM (NVRAM). The disclosed innovations have particular application to production database systems, where reducing database downtime in the event of a system crash is highly desirable. Embodiments of the disclosed technology can address a variety of problems that exist during a system crash. For example, embodiments of the disclosed technology can be used to address the loss of the physical memory mapping and/or the loss of the CPU cache that typically occurs in the event of a system crash. Furthermore, embodiments of the disclosed technology can be used to prevent data inconsistency and/or memory leak problems that may arise in the event of a system crash.

主权项

1. A method, comprising:
by a specialized memory allocator configured to assign portions of non-volatile RAM (NVRAM) for use by a program, the memory allocator being implemented by one or more processing devices:
writing first data to a memory allocator microlog, the first data including a first state ID indicating that the memory allocator is in a first state;performing a first memory allocation operation, the first memory allocation operation corresponding to the first state;writing second data to the memory allocator microlog, the second data replacing the first data and including a second state ID indicating that the memory allocator is in a second state; andperforming a second memory allocation operation, the second memory allocation operation corresponding to the second state.