[MAPREDUCE-6143] add configuration for mapreduce speculative execution in MR2

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.5.1
• Fix Version/s: 2.7.0
• Component/s: mrv2
• Hadoop Flags: Reviewed
• Assignee: Zhihai Xu
• Reporter: Zhihai Xu
• Created: 30/Oct/14 04:20
• Updated: 24/Apr/15 23:15
• Resolved: 02/Feb/15 21:54

Description

add configuration for mapreduce speculative execution in MR2.
Currently mapreduce.job.speculative.speculativecap and mapreduce.job.speculative.slownodethreshold are not used for MR2 mapreduce speculative execution any more.

We should make the following hardcode constants in DefaultSpeculator configurable for MR2 Map Reduce speculative execution:

private static final long SOONEST_RETRY_AFTER_NO_SPECULATE = 1000L * 1L;
private static final long SOONEST_RETRY_AFTER_SPECULATE = 1000L * 15L;
private static final double PROPORTION_RUNNING_TASKS_SPECULATABLE = 0.1;
private static final double PROPORTION_TOTAL_TASKS_SPECULATABLE = 0.01;
private static final int MINIMUM_ALLOWED_SPECULATIVE_TASKS = 10;