Module Trace_fuchsia

Fuchsia trace collector.

This provides a collector for traces that emits data into a file using the compact binary Fuchsia trace format. This reduces the tracing overhead compared to trace-tef, at the expense of simplicity.

module Buf : sig ... end
module Buf_chain : sig ... end

A set of buffers in use, and a set of ready buffers

module Buf_pool : sig ... end
module Exporter : sig ... end

An exporter, takes buffers with fuchsia events, and writes them somewhere

module Subscriber : sig ... end
module Writer : sig ... end

Write fuchsia events into buffers.

type output = [
  1. | `File of string
  2. | `Exporter of Exporter.t
]
val subscriber : out:[< output ] -> unit -> Trace_subscriber.t
val collector : out:[< output ] -> unit -> Trace_core.collector

Make a collector that writes into the given output. See setup for more details.

val setup : ?out:[ output | `Env ] -> unit -> unit

setup () installs the collector depending on out.

  • parameter out

    can take different values:

    • regular output value to specify where events go
    • `Env will enable tracing if the environment variable "TRACE" is set.
  • If it's set to "1", then the file is "trace.fxt".
  • Otherwise, if it's set to a non empty string, the value is taken to be the file path into which to write.
val with_setup : ?out:[< output | `Env Env ] -> unit -> (unit -> 'a) -> 'a

with_setup () f (optionally) sets a collector up, calls f(), and makes sure to shutdown before exiting.