type t = 
|Realtime
|Monotonic
|Process_cpu
|Process_thread
val all : t list
val to_string : t -> string
val getres : (t -> Core.Std.Int63.t) Core.Std.Or_error.t
val gettime : (t -> Core.Std.Int63.t) Core.Std.Or_error.t
val min_interval : (t -> Core.Std.Int63.t) Core.Std.Or_error.t
val mean_gettime_cost : (measure:t -> using:t -> Core.Std.Int63.t) Core.Std.Or_error.t
module Time_stamp_counter : sig .. end
type t
val rdtsc : unit -> t
val rdtscp : unit -> t
val diff : t -> t -> int