MAINTAINING AND USING A CACHE OF CHILD-TO-PARENT MAPPINGS IN A CONTENT-ADDRESSABLE STORAGE SYSTEM

摘要

Techniques for maintaining and using cached child-to-parent mappings in a content-addressable storage system are provided. A cache of child-to-parent mappings is maintained. Each child-to-parent mapping corresponds to a particular chunk in a hierarchy of chunks stored in a content-addressable chunk store, and maps the particular chunk to a parent chunk in the hierarchy of chunks. The hierarchy of chunks includes a first root chunk associated with a file system volume. In response to a change to the file system volume that causes associating a new root chunk with the file system volume, the cache is updated by adding one or more first child-to-parent mappings based on traversing at least a portion of a current file system hierarchy from the new root chunk, and removing one or more second child-to-parent mappings based on traversing at least a portion of a prior file system hierarchy from the first root chunk.

主权项

1. A method comprising:
maintaining a cache of child-to-parent mappings; wherein each child-to-parent mapping corresponds to a particular chunk in a hierarchy of chunks stored in a content-addressable storage system, and maps the particular chunk to a parent chunk in the hierarchy of chunks; wherein the hierarchy of chunks includes a first root chunk associated with a file system volume; in response to a change to the file system volume that causes associating a new root chunk with the file system volume, updating the cache by adding one or more first child-to-parent mappings based on traversing at least a portion of a current file system hierarchy from the new root chunk, and removing one or more second child-to-parent mappings based on traversing at least a portion of a prior file system hierarchy from the first root chunk.