Quota(An Admin Feature)

  • There are  2-types of quotas:
    • Space Quota
    • Normal Quota

Space Quota

  • Setting the size of directory to fixed byte.
  • The space quota is valid for future files(i.e. existing+setQuota(future))

Commands for space quota

  • hadoop dfsadmin -setSpaceQuota 100 /folder
  • hadoop dfsadmin -clrSpaceQuota /folder

Normal Quota

  • Setting the number of files of a directory to fixed number.
  • The normal quota is valid for future file(i.e. existing+setQuota(future))

Commands for normal quota

  • hadoop dfsadmin -setQuota 3 /folder
  • hadoop dfsadmin -clrQuota /folder

Keypoints

  • Quotas will be used when hive compaction arises.
  • It deletes the old records and updates with new records if duplicates are found which takes large time called as compaction
  • command to check quota
    • hadoop fs -count -q -h -v /folder

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