[HDFS-2699] Store data and checksums together in block file

• Type: Improvement
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Assignee: Dhruba Borthakur
• Reporter: Dhruba Borthakur
• Created: 17/Dec/11 08:27
• Updated: 17/Apr/14 03:53

Description

The current implementation of HDFS stores the data in one block file and the metadata(checksum) in another block file. This means that every read from HDFS actually consumes two disk iops, one to the datafile and one to the checksum file. This is a major problem for scaling HBase, because HBase is usually bottlenecked on the number of random disk iops that the storage-hardware offers.

Issue Links

• relates to: HBASE-5074 support checksums in HBase block cache