WRITE-AHEAD STYLE LOGGING IN A PERSISTENT MEMORY DEVICE

摘要

The techniques disclosed herein improve performance of file system logging by writing log data to persistent memory instead of staging in RAM before writing to disk. In one embodiment, while the log is being written, checksums are inserted, such that during recovery, the checksums can be used to distinguish good log pages from bad log pages. In this way, good log pages can be evaluated to determine whether to roll a portion of a file system transaction forward, backward, or do nothing, while bad log pages can be safely ignored. Additionally or alternatively, non-temporal copies are employed when writing data to persistent memory, thereby reducing an amount of time log data is exposed to be lost in a crash.