Brent Fulgham wrote: > ... I have > updated the shootout build machine with parrot (0.3.1) and can start > running tests if any exist.
A few weeks ago I wrote Brent's "Ackermann" benchmark in Amber for Parrot. Ackermann is a heavily recursive benchmark. Brent reports benchmarks for Ack(3, 7), Ack(3, 8) and Ack(3, 9). Unfortunately I could only get to Ack(3, 6) before parrot aborted with "maximum recursion depth exceeded", at recursion depth 1000. The recursion limit of 1000 is assigned in inter_create.c and seems somewhat arbitrary. Is it likely to be raised in the future? Regards, Roger Browne PS: I have appended the source code in case anyone is interested: -- Computes the value of Ack(3,n), which is 2^(n+3)-3 -- Specify 'n' on the command line (defaults to 1). -- As used in the "Computer Language Shootout" benchmarks: -- http://shootout.alioth.debian.org/sandbox/benchmark.php?test=ackermann -- See also: http://en.wikipedia.org/wiki/Ackermann_function (Wikipedia) -- Performance results, 2005-11-22 using Amber 0.3.1, Fedora Core 4 Linux -- on a 3.2GHz Pentium: -- Ack(3,0): 5 -- in 0.156s -- Ack(3,1): 13 -- in 0.156s -- Ack(3,2): 29 -- in 0.168s -- Ack(3,3): 61 -- in 0.200s -- Ack(3,4): 125 -- in 0.348s -- Ack(3,5): 253 -- in 0.876s -- Ack(3,6): 509 -- in 3.040s -- Ack(3,7) and above failed: "maximum recursion depth exceeded" -- Above times include Amber-to-PIR compilation of about 0.1 second. args := ARGUMENTS if args.count = 1 then num := args.item(1) -- Take 'n' from the command line else num := 1 -- or use default of 1 for 'n'. end print("Ack(3,") print(num) print("): ") print_line(ack(3, num)) private args -- Command-line arguments num -- : INTEGER -- Ackermann number ack(m, n) -- m: INTEGER; n: INTEGER; returns INTEGER do result := if m = 0 then n + 1 elseif n = 0 then ack(m - 1, 1) else ack(m - 1, ack(m, (n - 1))) end end end
