查看Linux磁盘块大小

#encoding: utf-8
#author: walker
#date: 2017-04-13
#summary: 获取文件所在磁盘块大小
#sys.version: 2.7.6 (default, Mar 22 2014, 22:59:56) \n[GCC 4.8.2]

import os
import math

#获取文件所在磁盘块大小
#参数为：大于0B，没有空洞(hole)的文件
#返回值：若正常，返回块大小；否则，返回-1
def GetBlockSize(pathfile):
fileSize = os.path.getsize(pathfile)
print('%s fileSize:%d' % (pathfile, fileSize))
if fileSize < 1:
return -1

blockSize = 512
for i in range(1, 10):
cmd = 'du -B %d %s' % (blockSize, pathfile)
print('cmd:%s' % cmd)
outText = os.popen(cmd).read()
num = int(outText.split('\t')[0])
print('num:%d' % num)
if math.ceil(1.0*fileSize/blockSize) == num:
break
blockSize *= 2

return blockSize

walker@walker-vm:~/apue$ df -hT
文件系统                        类型      容量  已用  可用 已用% 挂载点
/dev/mapper/walker--vm--vg-root ext4       18G  2.5G   14G   16% /
none                            tmpfs     4.0K     0  4.0K    0% /sys/fs/cgroup
udev                            devtmpfs  987M  4.0K  987M    1% /dev
tmpfs                           tmpfs     200M  616K  199M    1% /run
none                            tmpfs     5.0M     0  5.0M    0% /run/lock
none                            tmpfs     998M     0  998M    0% /run/shm
none                            tmpfs     100M     0  100M    0% /run/user
/dev/sda1                       ext2      236M   37M  187M   17% /boot
walker@walker-vm:~/apue$ sudo tune2fs -l /dev/mapper/walker--vm--vg-root | grep Block
Block count:              4651008
Block size:               4096
Blocks per group:         32768