node-failure-detector

node-failure-detector is a node.js implementation of the Phi accrual failure detector.

This is commonly used to detect failure of a peer in a distributed system.

Example

var fd = require('failure-detector');
var fds = {};

server.on('message', function(msg) {
  var f;
  if (msg.type == "ping") {
    if (!fds[server.id]) {
      fds[server.id] = new fd.FailureDetector();
    }
    fds[server.id].report();
  }
});

setInterval(function() {
  var k;
  for (k in fds) {
    if (fds.hasOwnProperty(k)) {
      if (fds[k].phi() > 8) {
        console.error(k + ' has probably failed!');
      }
    }
  }
}, 1000);

Installation

$ npm install failure-detector

License

Original node-failure-detector code is under the MIT license, from Joyent.

Updates from Rackspace are under the Apache license.