[ruby-core:27243] GC::Profiler.result question

Question.

With this result:

> report = GC::Profiler.result
irb(main):013:0> GC::Profiler.report
GC 13 invokes.
Index    Invoke Time(sec)       Use Size(byte)     Total Size(byte)
     Total Object                    GC Time(ms)
    1               0.406              1402080              2785280
            87040        15.62500000000000000000
    2               2.094              1408800              2785280
            87040        15.62500000000000000000
    3               2.141              1409344              3211264
           100352        15.62500000000000000000
    4               2.156              1411488              3211264
           100352        15.62500000000000000000
    5               4.359              1414240              3211264
           100352         0.00000000000000000000
    6               4.375              1416416              3211264
           100352         0.00000000000000000000

why does it say 13 invokes when there appear to be 6?

Also, it appears that the "Invoke Time" is actually the number of user
cpu seconds the process has used since it started, i.e.

    1               0.422              1401984              2785280
            87040         0.00000000000000000000
# who knows how much time actually elapsed between these two--in this
instance it was 1 second with a "sleep 1" command
    2               0.453              1404544              2785280
            87040        15.62500000000000000000

I would have anticipated it outputting system time--is using
get_rusage there expected?  If so perhaps it should relable the column
as Invoke User Time or something.

Thanks.
-r