Python实现测试磁盘性能的方法

#!/usr/bin/python
# -*- coding: utf-8 -*-
filecount = 300000
filesize = 1024
import random, time
from os import system
flush = "sudo su -c 'sync ; echo 3 > /proc/sys/vm/drop_caches'"
randfile = open("/dev/urandom", "r")
print "\ncreate test folder:"
starttime = time.time()
system("rm -rf test && mkdir test")
print time.time() - starttime
system(flush)
print "\ncreate files:"
starttime = time.time()
for i in xrange(filecount):
    rand = randfile.read(int(filesize * 0.5 + filesize * random.random()))
    outfile = open("test/" + unicode(i), "w")
    outfile.write(rand)
print time.time() - starttime
system(flush)
print "\nrewrite files:"
starttime = time.time()
for i in xrange(int(filecount / 10)):
    rand = randfile.read(int(filesize * 0.5 + filesize * random.random()))
    outfile = open("test/" + unicode(int(random.random() * filecount)), "w")
    outfile.write(rand)
print time.time() - starttime
system(flush)
print "\nread linear:"
starttime = time.time()
for i in xrange(int(filecount / 10)):
    infile = open("test/" + unicode(i), "r")
    outfile.write(infile.read());
print time.time() - starttime
system(flush)
print "\nread random:"
starttime = time.time()
outfile = open("/dev/null", "w")
for i in xrange(int(filecount / 10)):
    infile = open("test/" + unicode(int(random.random() * filecount)), "r")
    outfile.write(infile.read());
print time.time() - starttime
system(flush)
print "\ndelete all files:"
starttime = time.time()
system("rm -rf test")
print time.time() - starttime
system(flush)