Uploaded image for project: 'Lustre'
  1. Lustre
  2. LU-8235

Add pool awareness to lfs_migrate

    XMLWordPrintable

Details

    • New Feature
    • Resolution: Fixed
    • Minor
    • Lustre 2.11.0
    • Lustre 2.7.0, Lustre 2.5.3
    • 9223372036854775807

    Description

      The primary reason for this feature is to be able to allow users to specify where files are migrated to. The past focus of lfs_migrate seems to be to drain an OST and write objects to any and all other available targets. However, other use cases for lfs_migrate include rebalancing capacity, and moving data between tiers of storage with different performance characteristics.

      When new targets are added to a file system, it is beneficial to keep the allocation policy set such that active work will write new files that use ALL targets and retain performance; then old data can be identified with Robinhood or lfs find, and moved to the new targets with lfs_migrate. Adding pool awareness (with a "-p" command line option) would greatly facilitate this work, as all that would need to be done by the admin is to create a pool with the new targets in it.

      Note: additional (future) work to build on this and accomplish automatic capacity balancing would be to add another tool or two which:
      1) helps manage or automatically create one or more pools of "underused" targets
      2) finds old large files and runs lfs_migrate with an intelligently selected stripe count and pool name

      Attachments

        Issue Links

          Activity

            People

              sguminsx Steve Guminski (Inactive)
              eschnepp Eric Schnepp
              Votes:
              1 Vote for this issue
              Watchers:
              8 Start watching this issue

              Dates

                Created:
                Updated:
                Resolved: