[HDFS-2757] Cannot read a local block that's being written to when using the local read short circuit

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.0.0
• Fix Version/s: 1.2.0, 2.0.2-alpha, 0.23.6
• Hadoop Flags: Reviewed
• Assignee: Jean-Daniel Cryans
• Reporter: Jean-Daniel Cryans
• Created: 06/Jan/12 00:54
• Updated: 11/Jan/13 12:35
• Resolved: 09/Sep/12 06:45

Description

When testing the tail'ing of a local file with the read short circuit on, I get:

2012-01-06 00:17:31,598 WARN org.apache.hadoop.hdfs.DFSClient: BlockReaderLocal requested with incorrect offset:  Offset 0 and length 8230400 don't match block blk_-2842916025951313698_454072 ( blockLen 124 )
2012-01-06 00:17:31,598 WARN org.apache.hadoop.hdfs.DFSClient: BlockReaderLocal: Removing blk_-2842916025951313698_454072 from cache because local file /export4/jdcryans/dfs/data/blocksBeingWritten/blk_-2842916025951313698 could not be opened.
2012-01-06 00:17:31,599 INFO org.apache.hadoop.hdfs.DFSClient: Failed to read block blk_-2842916025951313698_454072 on local machine java.io.IOException:  Offset 0 and length 8230400 don't match block blk_-2842916025951313698_454072 ( blockLen 124 )
2012-01-06 00:17:31,599 INFO org.apache.hadoop.hdfs.DFSClient: Try reading via the datanode on /10.4.13.38:51010
java.io.EOFException: hdfs://sv4r11s38:9100/hbase-1/.logs/sv4r13s38,62023,1325808100311/sv4r13s38%2C62023%2C1325808100311.1325808100818, entryStart=7190409, pos=8230400, end=8230400, edit=5