[GOSSIP-74] FailureDetector is calculating phi improperly

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.1.3
• Assignee: Maxim Rusak
• Reporter: Maxim Rusak
• Created: 14/Mar/17 10:03
• Updated: 20/Mar/17 02:38
• Resolved: 20/Mar/17 02:22

Description

Now FailureDetector have (at least) 2 bugs (in comparation to original paper):
1. latestHeartbeatMs don't update on each HeartBeat. So we have descriptiveStatistics consisted not from deltas between heartbeats but from time periods from first heartbeats.
2. when we create normalDistribution we pass variation, not standard deviation.
They make FailureDetector totally indifferent due to extremely high deviation.
Example: http://pastebin.com/xaeF52PP
Here we send 100 heartbeats, one per second(for example), then we check the state after 2000 seconds, and comparing to threshold it's still alive.

Issue Links

• links to: GitHub Pull Request #43