[HDFS-2655] BlockReaderLocal#skip performs unnecessary IO

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.23.1, 2.0.0-alpha
• Fix Version/s: 0.23.2
• Component/s: datanode
• Hadoop Flags: Reviewed
• Assignee: Brandon Li
• Reporter: Eli Collins
• Created: 10/Dec/11 03:59
• Updated: 10/Mar/15 04:35
• Resolved: 16/Feb/12 19:11

Description

Per HDFS-2654 BlockReaderLocal#skip performs the skip by reading the data so we stay in sync with checksums. This could be implemented more efficiently in the future to skip to the beginning of the appropriate checksum chunk and then only read to the middle of that chunk.