[HDFS-11339] Support File IO sampling for Datanode IO profiling hooks

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 2.9.0, 3.0.0-alpha2
• Component/s: datanode
• Hadoop Flags: Reviewed
• Assignee: Hanisha Koneru
• Reporter: Hanisha Koneru
• Created: 13/Jan/17 18:33
• Updated: 17/Jan/17 07:36
• Resolved: 16/Jan/17 22:48

Description

HDFS-10958 introduces instrumentation hooks around DataNode disk IO and HDFS-10959 adds support for profiling hooks to expose latency statistics.
Instead of profiling all the file IO events, we can sample a fraction of the events and profile them. The fraction to be sampled can be configurable.