Systems and methods for portals into snapshot data
View Patent ↗In one embodiment, a user or client device communicates with a distributed file system comprised of one or more physical nodes. The data on each of the physical nodes store metadata about files and directories within the file system. Some of the embodiments permit a user to take a snapshot of data stored on the file system. The snapshot may include a single file, a single directory, a plurality of files within a directory, a plurality of directories, a path on the file system that includes nested files and subdirectories, or more than one path on the file system that each includes nested files and directories. In some embodiments, systems and methods intelligently choose whether to use copy-on-write or point-in-time copy when saving data in a snapshot version of a file whose current version is being overwritten. In some embodiments, systems and methods allow snapshot users to return from a snapshot directory to the immediate parent directory from which the user entered into the snapshot.
1. A method of ascending a file system capable of distinguishing, based on relative depth, between multiple unique paths to the same directory, the method comprising:
receiving, by a computer processor, a request to ascend from a child directory to an expected parent directory of a file system organized in a hierarchy, the expected parent directory being one of multiple possible parent directories;
determining, by a computer processor, the expected parent directory by evaluating, in part, a relative depth value of the child directory, wherein the relative depth value indicates how far the child directory is from a portal, wherein the portal is an entry point in the file system that is at the same level or a higher level than the expected parent directory in the hierarchy, the determining performed without the need to identify the path or the entry point; and
ascending, by a computer processor, to the expected parent directory,
wherein the file system is a multiple-version file system comprising current versions of data, snapshot versions of data, and portals to snapshots of data, and wherein the child directory is a snapshot version of data and wherein the relative depth value indicates how far the child directory is from its snapshot portal.
2. The method of claim 1 , wherein the ascending to the expected parent directory is part of ascending the file system through a path that was taken when descending the file system.
3. The method of claim 1 , wherein the file system is a distributed file system.
4. The method of claim 2 , wherein the file system is a distributed file system.
5. The method of claim 1 , wherein the snapshot versions of data are per-directory snapshots.
6. The method of claim 1 , further comprising calculating the relative depth when descending into the child directory.
7. The method of claim 1 , wherein the expected parent directory comprises one of the following: a snapshot version of data, a portal to snapshot data, and a current version of data.
8. The method of claim 1 , wherein the determining further comprises determining whether the child directory is one of the following: a current version of data, a portal to snapshot data, and a snapshot version of data.
9. A system capable of ascending a file system by distinguishing, based on relative depth, between multiple unique paths to the same directory, the system comprising:
a processor;
a memory system coupled to the processor, the memory system storing a file system organized in a hierarchy; and
a navigation module comprising instructions executable by the processor to cause operations to be performed on the file system, the operations comprising:
receiving a request to ascend from a child directory to an expected parent directory, the expected parent directory being one of multiple possible parent directories;
determining the expected parent directory by evaluating, in part, a relative depth value of the child directory, wherein the relative depth value indicates how far the child directory is from a portal, wherein the portal is an entry point that is at the same level or a higher level than the expected parent directory in the hierarchy, the determining performed without the need to identify the path or the entry point; and
ascending to the expected parent directory,
wherein the file system is a multiple-version file system comprising current versions of data, snapshot versions of data, and portals to snapshots of data, and wherein the child directory is a snapshot version of data, and wherein the relative depth value indicates how far the child directory is from its snapshot portal.
10. The system of claim 9 , wherein the ascending to the expected parent directory is part of ascending the file system through a path that was taken when descending the file system.
11. The system of claim 9 , wherein the file system is a distributed file system.
12. The system of claim 10 , wherein the file system is a distributed file system.
13. The system of claim 9 , wherein the snapshot versions of data are per-directory snapshots.
14. The system of claim 9 , wherein the instructions further comprise calculating the relative depth when descending into the child directory.
15. The system of claim 9 , wherein the expected parent directory comprises one of the following: a snapshot version of data, a portal to snapshot data, and a current version of data.
16. The system of claim 9 , wherein the determining further comprises determining whether the child directory is one of the following: a current version of data, a portal to snapshot data, and a snapshot version of data.