FIO是测试IOPS的非常好的工具，用来对硬件进行压力测试和验证，支持13种不同的I/O引擎，包括:sync,mmap, libaio, posixaio, SG v3, splice, null, network, syslet, guasi, solarisaio 等等。 
fio 官网地址：http://freshmeat.net/projects/fio/ 
一，FIO安装 
wget http://brick.kernel.dk/snaps/fio-2.0.7.tar.gz 
yum install libaio-devel 
tar -zxvf fio-2.0.7.tar.gz 
cd fio-2.0.7 
make 
make install 
二，随机读测试： 
随机读： 
fio -filename=/dev/sdb1 -direct=1 -iodepth 1 -thread -rw=randread -ioengine=psync -bs=16k -size=200G -numjobs=10 -runtime=1000 -group_reporting -name=mytest 
说明： 
filename=/dev/sdb1 测试文件名称，通常选择需要测试的盘的data目录。 
direct=1 测试过程绕过机器自带的buffer。使测试结果更真实。 
rw=randwrite 测试随机写的I/O 
rw=randrw 测试随机写和读的I/O 
bs=16k 单次io的块文件大小为16k 
bsrange=512-2048 同上，提定数据块的大小范围 
size=5g 本次的测试文件大小为5g，以每次4k的io进行测试。 
numjobs=30 本次的测试线程为30. 
runtime=1000 测试时间为1000秒，如果不写则一直将5g文件分4k每次写完为止。 
ioengine=psync io引擎使用pync方式 
rwmixwrite=30 在混合读写的模式下，写占30% 
group_reporting 关于显示结果的，汇总每个进程的信息。 
此外 
lockmem=1g 只使用1g内存进行测试。 
zero_buffers 用0初始化系统buffer。 
nrfiles=8 每个进程生成文件的数量。 
顺序读： 
fio -filename=/dev/sdb1 -direct=1 -iodepth 1 -thread -rw=read -ioengine=psync -bs=16k -size=200G -numjobs=30 -runtime=1000 -group_reporting -name=mytest 
随机写： 
fio -filename=/dev/sdb1 -direct=1 -iodepth 1 -thread -rw=randwrite -ioengine=psync -bs=16k -size=200G -numjobs=30 -runtime=1000 -group_reporting -name=mytest 
顺序写： 
fio -filename=/dev/sdb1 -direct=1 -iodepth 1 -thread -rw=write -ioengine=psync -bs=16k -size=200G -numjobs=30 -runtime=1000 -group_reporting -name=mytest 
混合随机读写： 
fio -filename=/dev/sdb1 -direct=1 -iodepth 1 -thread -rw=randrw -rwmixread=70 -ioengine=psync -bs=16k -size=200G -numjobs=30 -runtime=100 -group_reporting -name=mytest -ioscheduler=noop 
三，实际测试范例： 
[root@localhost ~]# fio -filename=/dev/sdb1 -direct=1 -iodepth 1 -thread -rw=randrw -rwmixread=70 -ioengine=psync -bs=16k -size=200G -numjobs=30 -runtime=100 -group_reporting -name=mytest1 
mytest1: (g=0): rw=randrw, bs=16K-16K/16K-16K, ioengine=psync, iodepth=1 
... 
mytest1: (g=0): rw=randrw, bs=16K-16K/16K-16K, ioengine=psync, iodepth=1 
fio 2.0.7 
Starting 30 threads 
Jobs: 1 (f=1): [________________m_____________] [3.5% done] [6935K/3116K /s] [423 /190 iops] [eta 48m:20s] s] 
mytest1: (groupid=0, jobs=30): err= 0: pid=23802 
read : io=1853.4MB, bw=18967KB/s, iops=1185 , runt=100058msec 
clat (usec): min=60 , max=871116 , avg=25227.91, stdev=31653.46 
lat (usec): min=60 , max=871117 , avg=25228.08, stdev=31653.46 
clat percentiles (msec): 
| 1.00th=[ 3], 5.00th=[ 5], 10.00th=[ 6], 20.00th=[ 8], 
| 30.00th=[ 10], 40.00th=[ 12], 50.00th=[ 15], 60.00th=[ 19], 
| 70.00th=[ 26], 80.00th=[ 37], 90.00th=[ 57], 95.00th=[ 79], 
| 99.00th=[ 151], 99.50th=[ 202], 99.90th=[ 338], 99.95th=[ 383], 
| 99.99th=[ 523] 
bw (KB/s) : min= 26, max= 1944, per=3.36%, avg=636.84, stdev=189.15 
write: io=803600KB, bw=8031.4KB/s, iops=501 , runt=100058msec 
clat (usec): min=52 , max=9302 , avg=146.25, stdev=299.17 
lat (usec): min=52 , max=9303 , avg=147.19, stdev=299.17 
clat percentiles (usec): 
| 1.00th=[ 62], 5.00th=[ 65], 10.00th=[ 68], 20.00th=[ 74], 
| 30.00th=[ 84], 40.00th=[ 87], 50.00th=[ 89], 60.00th=[ 90], 
| 70.00th=[ 92], 80.00th=[ 97], 90.00th=[ 120], 95.00th=[ 370], 
| 99.00th=[ 1688], 99.50th=[ 2128], 99.90th=[ 3088], 99.95th=[ 3696], 
| 99.99th=[ 5216] 
bw (KB/s) : min= 20, max= 1117, per=3.37%, avg=270.27, stdev=133.27 
lat (usec) : 100=24.32%, 250=3.83%, 500=0.33%, 750=0.28%, 1000=0.27% 
lat (msec) : 2=0.64%, 4=3.08%, 10=20.67%, 20=19.90%, 50=17.91% 
lat (msec) : 100=6.87%, 250=1.70%, 500=0.19%, 750=0.01%, 1000=0.01% 
cpu : usr=1.70%, sys=2.41%, ctx=5237835, majf=0, minf=6344162 
IO depths : 1=100.0%, 2=0.0%, 4=0.0%, 8=0.0%, 16=0.0%, 32=0.0%, >=64=0.0% 
submit : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0% 
complete : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0% 
issued : total=r=118612/w=50225/d=0, short=r=0/w=0/d=0 
Run status group 0 (all jobs): 
READ: io=1853.4MB, aggrb=18966KB/s, minb=18966KB/s, maxb=18966KB/s, mint=100058msec, maxt=100058msec 
WRITE: io=803600KB, aggrb=8031KB/s, minb=8031KB/s, maxb=8031KB/s, mint=100058msec, maxt=100058msec 
Disk stats (read/write): 
sdb: ios=118610/50224, merge=0/0, ticks=2991317/6860, in_queue=2998169, util=99.77% 
主要查看以上粗体部分的iops