Tracer Collector Stage

This stage enables the profiler (see the section on profiling) and periodically polls the TracerHost for scope information. This information is packed into an rbuf and transmitted, allowing you to visualize it in a GUI or log it for future analysis.


The collector will, by default, not emit anything on shutdown. You can configure it to emit either a ‘Summary’ report or a ‘Json’ report on exit.

This will be dumped to stdout. The summary report is a table showing min/max/average and count information on scopes, while the JSON report is a report suitable for loading within the Chrome tracing tooling.


The stage runs at about 0.2Hz and emits reports periodically. It does not offer any control.


There are no special metrics. The report is emitted on /scope_timing_reports periodically.