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  1. Lustre
  2. LU-10957

Return more lock bits from MDS for open-create

Details

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

    Description

      Currently we return only layout lock for any open. With patches from LU-10948 we'll also return a lookup lock.

      But I suspect on a successful create we should return a full set of bits except perhaps open lock - this would allow the name to be hashed and cache the attributes too.

      In workloads like mdtest it's kind of important because after initial create the subsequent stat would be a 100% local operation as opposed to going to the server for a lookup or inode attrs revalidate.

      There are basically no downsides. If we do create and then a lot of clients do conflicting things to the file - that's a single lock cancel to matter what anyway.

      Attachments

        Issue Links

          is related to

          Bug - A problem which impairs or prevents the functions of the product. LU-11199 mdsrate open() performance degradation

          • Major - Major loss of function.
          • Resolved
          is related to

          Improvement - An improvement or enhancement to an existing feature or task. LU-10948 client cache open lock after N opens

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

          Activity

            [LU-10957] Return more lock bits from MDS for open-create
            adilger Andreas Dilger made changes -
            Link New: This issue is related to DDN-799 [ DDN-799 ]
            paf Patrick Farrell (Inactive) made changes -
            Link New: This issue is related to LU-11199 [ LU-11199 ]
            adilger Andreas Dilger made changes -
            Link New: This issue is related to LU-10948 [ LU-10948 ]
            green Oleg Drokin made changes -
            Description New: Currently we return only layout lock for any open. With patches from LU-10948 we'll also return a lookup lock.

            But I suspect on a successful create we should return a full set of bits except perhaps open lock - this would allow the name to be hashed and cache the attributes too.

            In workloads like mdtest it's kind of important because after initial create the subsequent stat would be a 100% local operation as opposed to going to the server for a lookup or inode attrs revalidate.

            There are basically no downsides. If we do create and then a lot of clients do conflicting things to the file - that's a single lock cancel to matter what anyway.
            green Oleg Drokin created issue -

            People

              wc-triage WC Triage
              green Oleg Drokin
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              Dates

                Created:
                Updated: