Multi-level Visualization of Concurrent and Distributed Computation in Erlang

This paper describes a prototype visualization system

for concurrent and distributed applications programmed

using Erlang, providing two levels of granularity of view. Both

visualizations are animated to show the dynamics of aspects of

the computation.

At the low level, we show the concurrent behaviour of the

Erlang schedulers on a single instance of the Erlang virtual

machine, which we call an Erlang node. Typically there will be

one scheduler per core on a multicore system. Each scheduler

maintains a run queue of processes to execute, and we visualize

the migration of Erlang concurrent processes from one run queue

to another as work is redistributed to fully exploit the hardware.

The schedulers are shown as a graph with a circular layout. Next

to each scheduler we draw a variable length bar indicating the

current size of the run queue for the scheduler.

At the high level, we visualize the distributed aspects of the

system, showing interactions between Erlang nodes as a dynamic

graph drawn with a force model. Speci?cally we show message

passing between nodes as edges and lay out nodes according to

their current connections. In addition, we also show the grouping

of nodes into “s_groups” using an Euler diagram drawn with

circles.