6 Monitoring Tools

To help the programmer understand, tune, and debug distributed applications Mozart provides three tools for understanding the behavior of the DS.

6.1 The Distribution Panel

The Distribution Panel periodically retrieves the internal state of the Distribution Subsystem. The information is then displayed in a graphical tool (see Figure 6.1 and ``Distribution Panel''). The Distribution Panel enables monitoring the behavior of a Mozart site in runtime. Information of currently known remote sites, exported entities, imported entities, sent messages summarized by message type, and marshaling information is displayed.

Figure 6.1: An example of the Distribution Panel.

6.2 The Oz Message Tracer

The tool merges logs from different Mozart engines doing distributed computation. The logs are sorted in the casual order imposed by their internal message sending and receiving, and displayed graphically (see Figure 6.2). From the visualization of the casual order of events in a distributed computation the behavior of a set of Mozart sites can be examined in detail. The OzMessageTracer is available via Mogul.

Figure 6.2: An example of the LogTool.

6.3 The Mozart Distribution-Subsystem Simulator

The simulator is a graphical tool (see Figure 6.3) for development and understanding of networked programming languages. It enables simulation of a set of communicating virtual machines in a controlled environment.

By giving the developer a tool where execution can be controlled, statistics can be retrieved and faults can be inserted, the simulator simplifies verification of new features for a networked programming language.

Figure 6.3: An example of the Simulator.

Erik Klintskog and Anna Neiderud
Version 1.4.0 (20080702)