[HBASE-7408] Make compaction to use pread instead of sequential read

• Type: Improvement
• Status: Closed
• Priority: Minor
• Resolution: Abandoned
• Assignee: Unassigned
• Reporter: Rishit Shroff
• Created: 20/Dec/12 18:43
• Updated: 15/Jun/22 21:07
• Resolved: 25/Jan/16 18:23

Description

As we discovered lately, HFile compactions use sequential reads to fetch blocks. It cause unwanted streaming of data from HDFS to region servers when there is a cache hit. Lets change to use preads to reduce iops on disks.