src/Pure/ML-Systems/timing.ML
author wenzelm
Thu Oct 01 23:27:05 2009 +0200 (2009-10-01)
changeset 32843 c8f5a7c8353f
parent 31757 c1262feb61c7
child 32935 2218b970325a
permissions -rw-r--r--
moved cache_conv to src/Pure/conv.ML, use Thm.cterm_cache;
     1 (*  Title:      Pure/ML-Systems/timing.ML
     2     Author:     Makarius
     3 
     4 Compiler-independent timing functions.
     5 *)
     6 
     7 fun start_timing () =
     8   let
     9     val real_timer = Timer.startRealTimer ();
    10     val real_time = Timer.checkRealTimer real_timer;
    11     val cpu_timer = Timer.startCPUTimer ();
    12     val cpu_times = Timer.checkCPUTimes cpu_timer;
    13   in (real_timer, real_time, cpu_timer, cpu_times) end;
    14 
    15 fun end_timing (real_timer, real_time, cpu_timer, cpu_times) =
    16   let
    17     val real_time2 = Timer.checkRealTimer real_timer;
    18     val {nongc = {sys, usr}, gc = {sys = gc_sys, usr = gc_usr}} = cpu_times;
    19     val {nongc = {sys = sys2, usr = usr2}, gc = {sys = gc_sys2, usr = gc_usr2}} =
    20       Timer.checkCPUTimes cpu_timer;
    21 
    22     fun checked x y = Real.checkFloat y handle Overflow => x | Div => x;
    23 
    24     open Time;
    25     val elapsed = real_time2 - real_time;
    26     val gc = gc_usr2 - gc_usr + gc_sys2 - gc_sys;
    27     val cpu = usr2 - usr + sys2 - sys + gc;
    28     val gc_percent =
    29       Real.fmt (StringCvt.FIX (SOME 1)) (100.0 * checked 0.0 (toReal gc / toReal cpu));
    30     val factor =
    31       Real.fmt (StringCvt.FIX (SOME 2)) (checked 1.0 (toReal cpu / toReal elapsed));
    32     val message =
    33       (toString elapsed ^ "s elapsed time, " ^ toString cpu ^ "s cpu time, " ^
    34         gc_percent ^ "% GC time, factor " ^ factor) handle Time => "";
    35   in {message = message, elapsed = elapsed, cpu = cpu, gc = gc} end;
    36