root# fio --name=randread --rw=randread --bs=4k --ioengine=libaio --iodepth=64 --direct=1 --numjobs=1 --size=1G
randread: (g=0): rw=randread, bs=4K-4K/4K-4K, ioengine=libaio, iodepth=64
fio 1.59
Starting 1 process
Jobs: 1 (f=1): [r] [98.6% done] [20742K/0K /s] [5064 /0  iops] [eta 00m:07s]
randread: (groupid=0, jobs=1): err= 0: pid=31823
  read : io=1024.0MB, bw=2063.4KB/s, iops=515 , runt=508182msec
    slat (usec): min=9 , max=238 , avg=15.32, stdev= 3.57
    clat (usec): min=3 , max=5198.5K, avg=124050.36, stdev=251834.37
     lat (usec): min=16 , max=5198.6K, avg=124065.92, stdev=251835.77
    bw (KB/s) : min=  667, max=103842, per=99.29%, avg=2048.36, stdev=3861.47
  cpu          : usr=0.23%, sys=99.69%, ctx=2185, majf=0, minf=69
  IO depths    : 1=0.1%, 2=0.1%, 4=0.1%, 8=0.1%, 16=0.1%, 32=0.1%, >=64=100.0%
     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=0.1%, >=64=0.0%
     issued r/w/d: total=262144/0/0, short=0/0/0
     lat (usec): 4=0.01%, 10=28.56%, 20=18.97%, 50=17.88%, 100=4.63%
     lat (usec): 250=2.02%, 500=0.17%, 750=0.01%, 1000=0.01%
     lat (msec): 2=4.97%, 4=0.01%, 10=0.01%, 20=0.03%, 50=0.13%
     lat (msec): 100=0.29%, 250=1.31%, 500=4.89%, 750=14.65%, 1000=0.90%
     lat (msec): 2000=0.51%, >=2000=0.06%

Run status group 0 (all jobs):
   READ: io=1024.0MB, aggrb=2063KB/s, minb=2112KB/s, maxb=2112KB/s, mint=508182msec, maxt=508182msec

Disk stats (read/write):
  loop0: ios=260831/137, merge=0/5, ticks=32479636/918584, in_queue=33408644, util=100.00%

root# cat /proc/version 
Linux version 3.19.0-rc2-next20141231-1-loopmq-small (sedat.dilek@gmail.com@fambox) (gcc version 4.9.2 (Ubuntu 4.9.2-0ubuntu1~12.04) ) #1 SMP Thu Jan 1 00:07:54 CET 2015


-dileks // 31-DEC-2014