# Disk Iops Vs. Disk Bandwidth (A)

+ Disk IOPS
  + Stress test the IOPS of a disk using the FIO tool
    + Block size 32K
  + Stress test mode: sequential write write+random read (TIKV server recommendation: ≥ 10000 IOPS)

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Verify disk IOPS and disk bandwidth
The IOPS and bandwidth requirements for the disks are specified for different components in the table of recommended configurations for a production environment. In distributed systems, the overhead on the network is much greater than that of a single-instance system. In order to compensate for some of the overhead, we have disk performance requirements. So how do you know if your server's disk performance is up to par?

- Disk IOPS
Use the FIO tool to stress test the IOPS of a disk
  - Block size 32K
  - Stress test mode sequential write write+random read; TIKV server recommended ≥ 10000 IOPS
  - random read test

```
$ fio -ioengine=psync -bs=32k -fdatasync=1 -thread -rw=randread -size=10G -filename=fio_randread_test.txt -name='fio randread test' -iodepth=4 -runtime=60 -numjobs=4 -group_reporting --output-format=json --output=fio_randread_result.json
```

  - Mixed test of sequential write and random read

```
$ fio -ioengine=psync -bs=32k -fdatasync=1 -thread -rw=randrw -percentage_random=100,0 -size=10G -filename=fio_randread_write_test.txt -name='fio mixed randread and sequential write test' -iodepth=4 -runtime=60 -numjobs=4 -group_reporting --output-format=json --output=fio_randread_write_test.json
```

ATTENTION:
-filename: The file path specified by the parameter is located on the test disk