Volatile management

The /volatile area is managed by a software system that cleans up the area periodically in multiple steps listed below. The first two steps will always take place. The third and forth steps will been proceed if the total usage for all projects of the volatile area is still not below the target.

  1. All files that have not been used for more than 6 months will be deleted.
  2. If a project exceeds its quota and the Lustre file system reaches its deletion threshold, the least-recently-used (LRU) files will be deleted until the total usage of the project is below its quota.
  3. Each file is assigned a deletion index that combines the excess usage of a project over its reservation coupled with the period of time the file is modifed. The clean up process will delete files according to the index in a descending order until the total /volatile usage is below the managed area's target and Lustre space is under its deletion threshold.
  4. When Lustre total usage is reached to a critical point, additional file deletion will be performed (using file deletion index).