cluster2 is a node.js (>= 0.6.x) compatible multi-process management module. This module grew out of our needs in operationalizing node.js for ql.io at eBay. Built on node's cluster, cluster2 adds several safeguards and utility functions to help support real-world production scenarios:

Scriptable start, shutdown and stop flows
Worker monitoring for process deaths
Worker recycling
Graceful shutdown
Idle timeouts
Validation hooks (for other tools to monitor cluster2 apps)
Events for logging cluster activities
Exit with error code when the port is busy to fail start scripts
and more coming soon

Realize 99.999% uptime and higher performance, at a lower license and support cost than competing enterprise-class databases.