Simple disk throughput tests using dd utility

Disk throughput on a Linux/UNIX system can be tested using a "built in" file copy utility - dd. The output from dd shows disk read or write throughput based on the number of bytes copied and time spent.

For example, the following command shows write throughput:

Where:
if=/dev/zero - data source;
of=/root/testfile - target file;
bs=64K - number of bytes to read/write at a time ("block size");
count=100000 - number of blocks to read/write.

Read throughput can be evaluated by using the testfile created in the previous example as the source:

To get more accurate result create a script including dd and sync commands and then execute the script using the time command.

To calculate the throughput divide the number of bytes reported by dd by the elapsed time reported by time:
6553600000 bytes / 1:13.66 = 6553600000 bytes / 73.66 s = 88970947.6 bytes/s = 88.97 MB/s or 84.85 MiB/s

For Windows users - there is always Iometer.