Maintaining and recomputing reference counts in a persistent memory file system
US11422903B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 30, 2020 |
| Grant date | Aug 23, 2022 |
| Priority date | — |
| Expiry date | Feb 10, 2041 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F2201/88
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Techniques are provided for maintaining and recomputing reference counts in a persistent memory file system of a node. Primary reference counts are maintained for pages within persistent memory of the node. In response to receiving a first operation to link a page into a persistent memory file system of the persistent memory, a primary reference count of the page is incremented before linking the page into the persistent memory file system. In response to receiving a second operation to unlink the page from the persistent memory file system, the page is unlinked from the persistent memory file system before the primary reference count is decremented. Upon the node recovering from a crash, the persistent memory file system is traversed in order to update shadow reference counts for the pages with correct reference count values, which are used to overwrite the primary reference counts with the correct reference count values.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.