tahoe-lafs/pyfec/fec/test/bench_pyfec.py

88 lines
3.0 KiB
Python

# pyfec -- fast forward error correction library with Python interface
#
# Copyright (C) 2007 Allmydata, Inc.
# Author: Zooko Wilcox-O'Hearn
# mailto:zooko@zooko.com
#
# This file is part of pyfec.
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
import fec
import array
def bench_encode_to_files_shuffle_decode_from_files():
FILESIZE=1000000
CHUNKSIZE=4096
PREFIX="testshare"
K=25
M=100
import os, time
left=FILESIZE
outfile = open("tmpranddata", "wb")
try:
while left:
d = os.urandom(min(left, CHUNKSIZE))
outfile.write(d)
left -= len(d)
outfile.flush()
outfile = None
infile = open("tmpranddata", "rb")
st = time.time()
fec.filefec.encode_to_files(infile, PREFIX, K, M)
so = time.time()
print "Encoded %s byte file into %d share files in %0.2f seconds, or %0.2f million bytes per second" % (FILESIZE, M, so-st, FILESIZE/((so-st)*1000000),)
enctime = so-st
# Now delete m-k of the tempfiles at random.
tempfs = [ f for f in os.listdir(".") if f.startwith(PREFIX) ]
tempfs.shuffle()
for victimtempf in tempfs[:M-K]:
os.remove(victimtempf)
recoveredfile = open("tmpranddata-recovered", "wb")
st = time.time()
fec.filefec.decode_from_files(recoveredfile, PREFIX, K, M)
so = time.time()
print "Encoded %s byte file from %d share files in %0.2f seconds, or %0.2f million bytes per second" % (FILESIZE, K, so-st, FILESIZE/((so-st)*1000000),)
return enctime + (so-st)
finally:
# os.remove("tmpranddata")
pass
def bench_read_encode_and_drop():
FILESIZE=1000000
CHUNKSIZE=4096
import os, time
left=FILESIZE
outfile = open("tmpranddata", "wb")
try:
while left:
d = os.urandom(min(left, CHUNKSIZE))
outfile.write(d)
left -= len(d)
outfile.flush()
outfile = None
infile = open("tmpranddata", "rb")
def cb(s, l):
pass
st = time.time()
fec.filefec.encode_file(infile, cb, 25, 100, 4096)
so = time.time()
print "Encoded %s byte file in %0.2f seconds, or %0.2f million bytes per second" % (FILESIZE, so-st, FILESIZE/((so-st)*1000000),)
return so-st
finally:
os.remove("tmpranddata")