doc/guide/src/MLtonRusage.adoc

   1 MLtonRusage
   2 ===========
   3
   4 [source,sml]
   5 ----
   6 signature MLTON_RUSAGE =
   7    sig
   8       type t = {utime: Time.time, (* user time *)
   9                 stime: Time.time} (* system time *)
  10
  11       val measureGC: bool -> unit
  12       val rusage: unit -> {children: t, gc: t, self: t}
  13    end
  14 ----
  15
  16 * `type t`
  17 +
  18 corresponds to a subset of the C `struct rusage`.
  19
  20 * `measureGC b`
  21 +
  22 controls whether garbage collection time is separately measured during
  23 program execution.  This affects the behavior of both `rusage` and
  24 `Timer.checkCPUTimes`, both of which will return gc times of zero with
  25 `measureGC false`.  Garbage collection time is always measured when
  26 either `gc-messages` or `gc-summary` is given as a
  27 <:RunTimeOptions:runtime system option>.
  28
  29 * `rusage ()`
  30 +
  31 corresponds to the C `getrusage` function.  It returns the resource
  32 usage of the exited children, the garbage collector, and the process
  33 itself.  The `self` component includes the usage of the `gc`
  34 component, regardless of whether `measureGC` is `true` or `false`.  If
  35 `rusage` is used in a program, either directly, or indirectly via the
  36 `Timer` structure, then `measureGC true` is automatically called at
  37 the start of the program (it can still be disable by user code later).