Copy On Write with reflink mechanism












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I have some question about reflinks in XFS:




  1. When copying a file from source to target, does it takes up any space? Meaning a 1MB file + its reflink = 2MB OR 1MB.

  2. What happens if the source gets modified? Does the reflink gets modified or the link will be disconnected and removed?

  3. What happens if the reflink gets modified? Does only the modified part get saved on storage?

  4. What happens if the source gets removed?

  5. What happens if the reflink gets removed?

  6. If the storage gets mounted by NFS on a client, are the reflinks accessible there? (Is this relevant?)

  7. Is there any performance difference between accessing files that are reflinks and accessing normal files?






xfs







share|improve this question





























    0














    I have some question about reflinks in XFS:




    1. When copying a file from source to target, does it takes up any space? Meaning a 1MB file + its reflink = 2MB OR 1MB.

    2. What happens if the source gets modified? Does the reflink gets modified or the link will be disconnected and removed?

    3. What happens if the reflink gets modified? Does only the modified part get saved on storage?

    4. What happens if the source gets removed?

    5. What happens if the reflink gets removed?

    6. If the storage gets mounted by NFS on a client, are the reflinks accessible there? (Is this relevant?)

    7. Is there any performance difference between accessing files that are reflinks and accessing normal files?






    xfs







    share|improve this question



























      0












      0








      0







      I have some question about reflinks in XFS:




      1. When copying a file from source to target, does it takes up any space? Meaning a 1MB file + its reflink = 2MB OR 1MB.

      2. What happens if the source gets modified? Does the reflink gets modified or the link will be disconnected and removed?

      3. What happens if the reflink gets modified? Does only the modified part get saved on storage?

      4. What happens if the source gets removed?

      5. What happens if the reflink gets removed?

      6. If the storage gets mounted by NFS on a client, are the reflinks accessible there? (Is this relevant?)

      7. Is there any performance difference between accessing files that are reflinks and accessing normal files?






      xfs







      share|improve this question















      I have some question about reflinks in XFS:




      1. When copying a file from source to target, does it takes up any space? Meaning a 1MB file + its reflink = 2MB OR 1MB.

      2. What happens if the source gets modified? Does the reflink gets modified or the link will be disconnected and removed?

      3. What happens if the reflink gets modified? Does only the modified part get saved on storage?

      4. What happens if the source gets removed?

      5. What happens if the reflink gets removed?

      6. If the storage gets mounted by NFS on a client, are the reflinks accessible there? (Is this relevant?)

      7. Is there any performance difference between accessing files that are reflinks and accessing normal files?






      xfs




      xfs






      share|improve this question















      share|improve this question













      share|improve this question




      share|improve this question








      edited 5 mins ago

























      asked 10 mins ago









      Ali Sh

      102




      102



























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