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  1. Lustre
  2. LU-11657

Prefetch whole ZFS block into client cache on random read

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Details

    • Improvement
    • Resolution: Unresolved
    • Minor
    • None
    • Lustre 2.13.0
    • None
    • 9223372036854775807

    Description

      When doing random read IOPS to a ZFS-backed OST, the ZFS code will read the whole ZFS block from disk in order to do data checksum verification on the whole block. We may as well align the client read to the ZFS blocksize and fetch the whole ZFS block into client RAM so that the client could re-use those blocks if the file is small enough to fit into RAM. That avoids extra IO on the server that is not being used.

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          is related to

          Improvement - An improvement or enhancement to an existing feature or task. LU-8591 allow specifying ZFS blocksize via ladvise

          • Minor - Minor loss of function, or other problem where easy workaround is present.
          • Open

          Improvement - An improvement or enhancement to an existing feature or task. LU-11416 Improve readahead for random read of small/medium files

          • Minor - Minor loss of function, or other problem where easy workaround is present.
          • Open

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              wc-triage WC Triage
              adilger Andreas Dilger
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              Dates

                Created:
                Updated: