- ONTAP 9 and later
- When there are tens or hundreds of millions of file and directory inodes, Phase I of dump can take a long time to complete.
- By default, the dump process that reads a file system for backup performs 'inode walk', where it references the volume-level inode table entries.
- The volume level inodes are still scanned when a subdirectory is specified as the file system to back up.
- For customers using qtrees to organize data on volumes, rather than subdirectories, configuring dump to perform 'tree walk' rather than inode walk can reduce Phase I times.
- The 'tree walk' or 'logical path find' can be faster than inode walk, as dump will reference only the root volume of a qtree when scanning for inodes to back up.
- Customers that are not using qtrees will see no benefit from configuring dump to perform 'tree walk'
- Before configuring dump to perform 'tree walk,' it is first necessary to create qtrees, and then move data from subdirectories into their new, corresponding qtrees. Depending on the amount of data to be moved into qtrees, re-organizing the data in such a way can be time consuming.