Pinba is a realtime PHP monitoring tool that accumulates and processes data sent over UDP by multiple PHP processes, and provides access to the data using MySQL. It also allows you to measure particular parts of the code using timers with arbitrary tags.
Watchy is a distributed system for application and server monitoring. It can monitor processes and logs, be integrated into applications, and be integrated with Ganglia or MongoDB backends. A Web dashboard allows you to view realtime graphs.