sig

  type runtime_counter =
      EV_C_FORCE_MINOR_ALLOC_SMALL
    | EV_C_FORCE_MINOR_MAKE_VECT
    | EV_C_FORCE_MINOR_SET_MINOR_HEAP_SIZE
    | EV_C_FORCE_MINOR_MEMPROF
    | EV_C_MINOR_PROMOTED
    | EV_C_MINOR_ALLOCATED
    | EV_C_REQUEST_MAJOR_ALLOC_SHR
    | EV_C_REQUEST_MAJOR_ADJUST_GC_SPEED
    | EV_C_REQUEST_MINOR_REALLOC_REF_TABLE
    | EV_C_REQUEST_MINOR_REALLOC_EPHE_REF_TABLE
    | EV_C_REQUEST_MINOR_REALLOC_CUSTOM_TABLE
  type runtime_phase =
      EV_EXPLICIT_GC_SET
    | EV_EXPLICIT_GC_STAT
    | EV_EXPLICIT_GC_MINOR
    | EV_EXPLICIT_GC_MAJOR
    | EV_EXPLICIT_GC_FULL_MAJOR
    | EV_EXPLICIT_GC_COMPACT
    | EV_MAJOR
    | EV_MAJOR_SWEEP
    | EV_MAJOR_MARK_ROOTS
    | EV_MAJOR_MARK
    | EV_MINOR
    | EV_MINOR_LOCAL_ROOTS
    | EV_MINOR_FINALIZED
    | EV_EXPLICIT_GC_MAJOR_SLICE
    | EV_FINALISE_UPDATE_FIRST
    | EV_FINALISE_UPDATE_LAST
    | EV_INTERRUPT_REMOTE
    | EV_MAJOR_EPHE_MARK
    | EV_MAJOR_EPHE_SWEEP
    | EV_MAJOR_FINISH_MARKING
    | EV_MAJOR_GC_CYCLE_DOMAINS
    | EV_MAJOR_GC_PHASE_CHANGE
    | EV_MAJOR_GC_STW
    | EV_MAJOR_MARK_OPPORTUNISTIC
    | EV_MAJOR_SLICE
    | EV_MAJOR_FINISH_CYCLE
    | EV_MINOR_CLEAR
    | EV_MINOR_FINALIZERS_OLDIFY
    | EV_MINOR_GLOBAL_ROOTS
    | EV_MINOR_LEAVE_BARRIER
    | EV_STW_API_BARRIER
    | EV_STW_HANDLER
    | EV_STW_LEADER
    | EV_MAJOR_FINISH_SWEEPING
    | EV_MINOR_FINALIZERS_ADMIN
    | EV_MINOR_REMEMBERED_SET
    | EV_MINOR_REMEMBERED_SET_PROMOTE
    | EV_MINOR_LOCAL_ROOTS_PROMOTE
    | EV_DOMAIN_CONDITION_WAIT
    | EV_DOMAIN_RESIZE_HEAP_RESERVATION
  type lifecycle =
      EV_RING_START
    | EV_RING_STOP
    | EV_RING_PAUSE
    | EV_RING_RESUME
    | EV_FORK_PARENT
    | EV_FORK_CHILD
    | EV_DOMAIN_SPAWN
    | EV_DOMAIN_TERMINATE
  val lifecycle_name : Runtime_events.lifecycle -> string
  val runtime_phase_name : Runtime_events.runtime_phase -> string
  val runtime_counter_name : Runtime_events.runtime_counter -> string
  type cursor
  module Timestamp :
    sig type t val to_int64 : Runtime_events.Timestamp.t -> int64 end
  module Callbacks :
    sig
      type t
      val create :
        ?runtime_begin:(int ->
                        Runtime_events.Timestamp.t ->
                        Runtime_events.runtime_phase -> unit) ->
        ?runtime_end:(int ->
                      Runtime_events.Timestamp.t ->
                      Runtime_events.runtime_phase -> unit) ->
        ?runtime_counter:(int ->
                          Runtime_events.Timestamp.t ->
                          Runtime_events.runtime_counter -> int -> unit) ->
        ?alloc:(int -> Runtime_events.Timestamp.t -> int array -> unit) ->
        ?lifecycle:(int ->
                    Runtime_events.Timestamp.t ->
                    Runtime_events.lifecycle -> int option -> unit) ->
        ?lost_events:(int -> int -> unit) ->
        unit -> Runtime_events.Callbacks.t
    end
  val start : unit -> unit
  val pause : unit -> unit
  val resume : unit -> unit
  val create_cursor : (string * int) option -> Runtime_events.cursor
  val free_cursor : Runtime_events.cursor -> unit
  val read_poll :
    Runtime_events.cursor -> Runtime_events.Callbacks.t -> int option -> int
end