Collect [Tracy] profiles in tracing-enabled applications.
Assuming the application is well instrumented, this should in practice be a very low effort way
to gain great amounts of insight into an application performance.
Note, however that Tracy is ultimately a profiling, not an observability, tool. As thus, some
of tracing concepts cannot be represented well by Tracy. For instance, out-of-order span
entries and exits, are not supported, and neither are spans that are entered and exited on
different threads. This crate will attempt to mitigate the problems and retain trace validity
at the cost of potentially invalid data. When such a mitigation occurs, trace will contain a
message with a note about the problem.
Some other caveats to keep in mind:
* Only span entries and exits are recorded;
* Events show up as messages in Tracy, however Tracy can struggle with large numbers of
messages;
* Some additional functionality such as plotting and memory allocation profiling is only
available as part of the [tracy-client](tracy_client) crate.
# Important note
Unlike with many other subscriber implementations, simply depending on this crate is sufficient
for tracy to be enabled at program startup, even if [`TracyLayer`](TracyLayer) is not
registered as a subscriber. While not registering a `TracyLayer` will avoid Tracy from
collecting spans, it still broadcasts discovery packets to the local network and exposes the
data it collects in the background to that same network. Traces collected by Tracy may include
source and assembly code as well.
As thus, you may want make sure to only enable the `tracing-tracy` crate conditionally, via the
`enable` feature flag provided by this crate.
[Tracy]: https://github.com/wolfpld/tracy