performance measurements
Each table row shows performance measurements for this Python 3 program with a particular command-line input value N.
| N | CPU secs | Elapsed secs | Memory KB | Code B | ≈ CPU Load |
|---|---|---|---|---|---|
| 10 | 6.02 | 1.56 | 55,964 | 1271 | 94% 97% 5% 3% 1% 6% 93% 97% |
Read the ↓ make, command line, and program output logs to see how this program was run.
Read fannkuch-redux benchmark to see what this program should do.
notes
Python 3.3.1 (default, Apr 11 2013, 12:45:45) [GCC 4.7.2] on linux
fannkuch-redux Python 3 program source code
# The Computer Language Benchmarks Game
# http://benchmarksgame.alioth.debian.org/
#
# contributed by Miroslav Rubanets
# algorithm is based on Java 6 source code by Oleg Mazurov
# source is based on Miroslav Rubanets' C++ submission.
# converted to python by Ian P. Cooke
import sys
from multiprocessing import cpu_count, Pool
MAX_PROBLEM_SIZE = 12
MAX_CPU_LIMIT = 4
class Result:
def __init__(self, maxflips=0, checksum=0):
self.maxflips = maxflips
self.checksum = checksum
def accumulate(self, other):
self.maxflips = max( self.maxflips, other.maxflips );
self.checksum += other.checksum;
class PermutationGenerator:
def __init__(self, length, factorials, idx):
self.perm = [0] * MAX_PROBLEM_SIZE
self.count = [0] * MAX_PROBLEM_SIZE
self.length = length
self.factorials = factorials
self.first_permutation( idx )
def first_permutation( self, idx ):
pp = [0] * MAX_PROBLEM_SIZE
p = list(range(MAX_PROBLEM_SIZE))
for i in range( self.length - 1, 0, -1 ):
d = idx // self.factorials[i]
self.count[i] = d
idx = idx % self.factorials[i]
pp[:i+1] = p[:i+1]
for j in range(0, i+1):
if j+d <= i:
p[j] = pp[j+d]
else:
p[j] = pp[j+d-i-1]
self.perm[:self.length] = p[:self.length]
def next_permutation( self ):
#rotate
first = self.perm[0]
self.perm[0] = self.perm[1]
self.perm[1] = first
self.count[1] += 1
i=1
while self.count[i] > i:
self.count[i] = 0
i += 1
if i >= MAX_PROBLEM_SIZE:
break
self.count[i] += 1
#rotate
first = self.perm[0]
self.perm[:i] = self.perm[1:i+1]
self.perm[i] = first
def task_body( length, factorials, first_index, last_index ):
try:
g = PermutationGenerator(length, factorials, first_index)
maxflips = 0
checksum = 0
for i in range(first_index, last_index):
data = [0] * MAX_PROBLEM_SIZE
flips = 0;
f = g.perm[0];
if f > 0:
data[:length] = g.perm[:length]
while True:
data[:f+1] = data[f::-1] #reverse
flips += 1
f = data[0]
if f == 0:
break
maxflips = max(maxflips, flips)
checksum += flips if i%2 == 0 else -flips
g.next_permutation()
except:
import traceback; traceback.print_exc()
return Result(maxflips=maxflips, checksum=checksum)
def create_factorials(length):
factorials = [0] * (MAX_PROBLEM_SIZE+1)
factorials[0] = 1
for i in range(1, length+1):
factorials[i] = factorials[i-1]*i;
return factorials
usage = """usage fannkuchredux number
number has to be in range [3-12]\n""";
def main():
if len(sys.argv) < 2:
print(usage)
return 1
length = int(sys.argv[1])
if length < 3 or length > MAX_PROBLEM_SIZE:
print(usage)
return 2
n = min( cpu_count(), MAX_CPU_LIMIT )
processors = Pool(processes=n)
factorials = create_factorials(length)
result = Result()
index = 0
index_max = factorials[length]
index_step = (index_max + n-1) // n
for i in range(0,n):
processors.apply_async(task_body, [ length, factorials, index, index + index_step], callback=result.accumulate)
index += index_step
processors.close()
processors.join()
processors.terminate()
print("%d\nPfannkuchen(%d) = %d" % ( result.checksum, length, result.maxflips) )
return 0
main()
make, command-line, and program output logs
Sun, 30 Jul 2023 10:49:49 GMT COMMAND LINE: /usr/bin/python3 fannkuchredux.python3 10 PROGRAM OUTPUT: 73196 Pfannkuchen(10) = 38