Gerrit

A Web based code review and project management system for Git projects

     

linux windows osx open-source scm java

Instrumental

Instrumental is a real-time, high-scale application and server monitoring tool with intelligent alerts, a powerful query language, and free development accounts.

     

linux windows oxs free metrics commercial metrics monitoring visualization php ruby python net java nodejs

KairosDB

KairosDB is a fast distributed scalable time series database written on top of Cassandra. RESTful JSON-based query/results. Includes flot-based visualization.

     

linux windows osx open-source metrics visualization java cassandra

Monit

An open source utility for managing and monitoring processes, programs, files, directories and filesystems

     

linux osx open-source monitoring process-mgmt c