catapult 0.1 · OCaml Package

Profiling probes.

This is the main API. The user can insert probes into their code, and at runtime, these probes will use the Backend (if present) to emit tracing events to be replayed later. If no backend is present, the probes will do nothing.

type backend = (module Catapult__.Backend.S)

type arg = [

| `Int of int
| `String of string
| `Float of float
| `Bool of bool
| `Null

]

type 'a emit_fun_base =
  ?cat:string list ->
  ?pid:int ->
  ?tid:int ->
  ?args:(string * arg) list ->
  string ->
  'a

Emitter function, without timestamp. See emit_fun for more details.

type 'a emit_fun = ?ts_us:float -> 'a emit_fun_base

An emitter function. The positional string argument is the name.

parameter cat
list of categories for filtering the event

parameter pid
the process ID

parameter tid
the thread ID

parameter arguments
list of arguments for the event, with a name for each

parameter ts_us
timestamp in microseconds

parameter name
the name of this event

type 'a with_stack = ?stack:string list -> 'a

Function that can take a stack trace

type span_start

Represents the beginning of a span, to emit compact spans

val null_span : span_start

val enabled : unit -> bool

Is tracing enabled?

val emit : (?dur:float -> Event_type.t -> unit) emit_fun with_stack

Emit a generic event.

val begin_ : unit -> span_start

val exit : (span_start -> unit) emit_fun_base with_stack

Emit a "X" event with duration computed from the given span start

val with_ : ((unit -> 'a) -> 'a) emit_fun_base

val with1 : (('a -> 'b) -> 'a -> 'b) emit_fun_base

val with2 : (('a -> 'b -> 'c) -> 'a -> 'b -> 'c) emit_fun_base

val with3 : (('a -> 'b -> 'c -> 'd) -> 'a -> 'b -> 'c -> 'd) emit_fun_base

val begin' : unit emit_fun with_stack

Emit a "B" event

val exit' : unit emit_fun with_stack

Emit a "E" event

val span : (dur:float -> unit) emit_fun with_stack

Emit a "X" event

val obj_new : (id:string -> unit) emit_fun with_stack

val obj_snap : (snapshot:string -> id:string -> unit) emit_fun with_stack

val obj_delete : (id:string -> unit) emit_fun with_stack

val obj_with : (id:string -> (unit -> 'a) -> 'a) emit_fun

val obj_with1 : (id:string -> ('a -> 'b) -> 'a -> 'b) emit_fun

val a_begin : (id:string -> unit) emit_fun

val a_exit : (id:string -> unit) emit_fun

val a_snap : (id:string -> unit) emit_fun

val a_with : (id:string -> (unit -> 'a) -> 'a) emit_fun

val a_with1 : (id:string -> ('a -> 'b) -> 'a -> 'b) emit_fun

val f_begin : (id:string -> unit) emit_fun

val f_exit : (id:string -> unit) emit_fun

val f_step : (id:string -> unit) emit_fun

val instant : unit emit_fun with_stack

val counter : (cs:(string * int) list -> unit) emit_fun

val meta_thread_name : string -> unit

val meta_process_name : string -> unit

val tick : unit -> unit

Depending on the tracing backend, this needs to be called regularly to ensure background work is done.

module Syntax : sig ... end

include module type of Syntax

val let@ : ('a -> 'b) -> 'a -> 'b

module Control : sig ... end

Controls the current backend.

package catapult