From this article you’ll learn how to measure an input/output performance of a file system on such devices as HDD, SSD, USB Flash Drive etc.
I’ll show how to test the read/write speed of a disk from the Linux command line using dd command.
I’ll also show how to install and use hdparm utility for measuring read speed of a disk on Linux Mint, Ubuntu, Debian, CentOS, RHEL.
To get the accurate read/write speed, you should repeat the below tests several times (usually 3-5) and take the average result.
Cool Tip: How to choose SSD with the best quality/price relation! Read more →
dd: TEST Disk WRITE Speed
Run the following command to test the WRITE speed of a disk:
$ sync; dd if=/dev/zero of=tempfile bs=1M count=1024; sync
1024+0 records in
1024+0 records out
1073741824 bytes (1.1 GB) copied, 3.28696 s, 327 MB/s
dd: TEST Disk READ Speed
To get the real speed, we have to clear cache.
Run the following command to find out the READ speed from buffer:
$ dd if=tempfile of=/dev/null bs=1M count=1024
1024+0 records in
1024+0 records out
1073741824 bytes (1.1 GB) copied, 0.159273 s, 6.7 GB/s
Clear the cache and accurately measure the real READ speed directly from the disk:
$ sudo /sbin/sysctl -w vm.drop_caches=3
vm.drop_caches = 3
$ dd if=tempfile of=/dev/null bs=1M count=1024
1024+0 records in
1024+0 records out
1073741824 bytes (1.1 GB) copied, 2.27431 s, 472 MB/s
dd: TEST Read/Write Speed of an External Drive
Cool Tip: Have added a new drive to /etc/fstab? No need to reboot! Mount it with one command! Read more →
To check the performance of some External HDD, SSD, USB Flash Drive or any other removable device or remote file-system, simply access the mount point and repeat the above commands.
Or you can replace tempfile with the path to your mount point e.g.:
$ sync; dd if=/dev/zero of=/media/user/MyUSB/tempfile bs=1M count=1024; sync
Reminder: All the above commands use the temporary file tempfile. Don’t forget to delete it when you complete the tests.
hdparm: Test HDD, SSD, USB Flash Drive’s Performance
And it can also be used as a simple benchmarking tool that allows to quickly find out the READ speed of a disk.
hdparm is available from standard repositories on the most Linux distributions.
Install hdparm depending on your Linux distribution.
Cool Tip: Troubleshooting an issue with a hard drive performance? It will be a good idea also to test download/upload Internet speed. It can be easily done from the Linux command line! Read more →
On Linux Mint, Ubuntu, Debian:
$ sudo apt-get install hdparm
On CentOS, RHEL:
$ sudo yum install hdparm
Run hdparm as follows, to measure the READ speed of a storage drive device /dev/sda:
$ sudo hdparm -Tt /dev/sda /dev/sda: Timing cached reads: 16924 MB in 2.00 seconds = 8469.95 MB/sec Timing buffered disk reads: 1386 MB in 3.00 seconds = 461.50 MB/sec
