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    • 9223372036854775807

    Description

      On direct I/O a client gets substantial amount of grants without consuming them so that direct I/O writes face with ENOSPC long before disk space is over.
      The below example shows how dd oflag=direct fails to write 400kb to ~70mb ost.

      [root@sl75master tests]# OSTSIZE=100000 sh llmount.sh
      ...
      Updated after 6s: wanted 'procname_uid' got 'procname_uid'
      disable quota as required
      [root@sl75master tests]# lfs df -h
      UUID                       bytes        Used   Available Use% Mounted on
      lustre-MDT0000_UUID       122.4M        1.9M      109.5M   2% /mnt/lustre[MDT:0]
      lustre-OST0000_UUID        69.4M        1.2M       61.4M   2% /mnt/lustre[OST:0]
      lustre-OST0001_UUID        69.4M        1.2M       61.4M   2% /mnt/lustre[OST:1]
      
      filesystem_summary:       138.9M        2.5M      122.7M   2% /mnt/lustre
      
      [root@sl75master tests]# dd if=/dev/zero of=/mnt/lustre/file bs=4k count=100 oflag=direct
      dd: error writing ‘/mnt/lustre/file’: No space left on device
      54+0 records in
      53+0 records out
      217088 bytes (217 kB) copied, 0.138233 s, 1.6 MB/s
      [root@sl75master tests]# 
      

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            [LU-12687] Fast ENOSPC on direct I/O
            adilger Andreas Dilger made changes -
            Link New: This issue is related to DDN-4885 [ DDN-4885 ]
            jhammond John Hammond made changes -
            Link New: This issue is related to LU-13847 [ LU-13847 ]
            adilger Andreas Dilger made changes -
            Link New: This issue is related to HP-287 [ HP-287 ]
            jamesanunez James Nunez (Inactive) made changes -
            Remote Link New: This issue links to "Page (Whamcloud Community Wiki)" [ 24974 ]
            jamesanunez James Nunez (Inactive) made changes -
            Remote Link New: This issue links to "Page (Whamcloud Community Wiki)" [ 24922 ]
            pjones Peter Jones made changes -
            Resolution New: Fixed [ 1 ]
            Status Original: Reopened [ 4 ] New: Resolved [ 5 ]
            pjones Peter Jones made changes -
            Fix Version/s New: Lustre 2.12.6 [ 14707 ]
            tappro Mikhail Pershin made changes -
            Link New: This issue is related to LU-13766 [ LU-13766 ]
            tappro Mikhail Pershin made changes -
            Link New: This issue is related to DDN-1419 [ DDN-1419 ]
            tappro Mikhail Pershin made changes -
            Resolution Original: Fixed [ 1 ]
            Status Original: Resolved [ 5 ] New: Reopened [ 4 ]

            People

              vsaveliev Vladimir Saveliev
              vsaveliev Vladimir Saveliev
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              Dates

                Created:
                Updated:
                Resolved: