[HBASE-4989] Metrics to measure sequential reads and random reads separately

• Type: Improvement
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 0.94.0
• Component/s: regionserver
• Hadoop Flags: Incompatible change, Reviewed
• Release Note: The metric fsReadLatency records the number of sequential reads. The metric fsPreadLatency records the number of random reads.
• Assignee: Dhruba Borthakur
• Reporter: Dhruba Borthakur
• Created: 09/Dec/11 08:45
• Updated: 12/Oct/12 05:34
• Resolved: 12/Dec/11 18:22

Description

HBase does sequential reads for compactions and positional random reads for satisfying user's queries. It would be nice if we can measure their latencies separately. It is mostly the random reads that dominate a transactional workload.