[HDFS-445] pread() fails when cached block locations are no longer valid

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.20-append
• Fix Version/s: 0.20-append, 0.21.0
• Hadoop Flags: Reviewed
• Assignee: Kan Zhang
• Reporter: Kan Zhang
• Created: 24/Jun/09 22:23
• Updated: 24/Aug/10 20:48
• Resolved: 14/Jul/09 20:18

Description

when cached block locations are no longer valid (e.g., datanodes restart on different ports), pread() will fail, whereas normal read() still succeeds through re-fetching of block locations from namenode (up to a max number of times).