Test hard disk read/write speed in centos

This is on the server, and the read and write speed is extremely fast.

Write speed

$ Dd If =/dev/Zero BS = 1 k count = 1000000 of = 1gb. File

1000000 + 0 records in
1000000 + 0 records out
1024000000 bytes (1.0 GB) Copied, 5.13676 seconds, 199 MB/S

 

Read Speed

$ Dd If = 1gb. File BS = 64 k | dd OF =/dev/null

[Haibo @ localhost ~] $ Dd If = 1gb. File BS = 64 k | dd OF =/dev/null
15625 + 0 records in
15625 + 0 records out
1024000000 bytes (1.0 GB) Copied, 6.37813 seconds, 161 MB/S
2000000 + 0 records in
2000000 + 0 records out
1024000000 bytes (1.0 GB) Copied, 6.37891 seconds, 161 MB/S

 

Read/write speed

$ Dd If = 1 GB. File of = 2 GB. File BS = 64 K

15625 + 0 records in
15625 + 0 records out
1024000000 bytes (1.0 GB) Copied, 2.21364 seconds, 463 MB/

 

 

This is on a local VM.

[Root @ localhost ~] # Dd If =/dev/Zero BS = 1 k count = 1000000 of = 1gb. File
1000000 + 0 records in
1000000 + 0 records out
1024000000 bytes (1.0 GB) Copied, 39.6289 seconds, 25.8 MB/S
[Root @ localhost ~] #
[Root @ localhost ~] #
[Root @ localhost ~] # Dd If = 1gb. File BS = 64 k | dd OF =/dev/null
2000000 + 0 records in
2000000 + 0 records out
1024000000 bytes (1.0 GB) Copied, 39.8982 seconds, 25.7 MB/S
15625 + 0 records in
15625 + 0 records out
1024000000 bytes (1.0 GB) Copied, 39.9039 seconds, 25.7 MB/S
[Root @ localhost ~] # Dd If = 1 GB. File of = 2 GB. File BS = 64 K
15625 + 0 records in
15625 + 0 records out
1024000000 bytes (1.0 GB) Copied, 46.391 seconds, 22.1 MB/S

 

Linux4 uses time for timing

[XXX] $ TIME dd If =/dev/Zero BS = 1 k count = 1000000 of = 1 GB. File

1000000 + 0 records in

1000000 + 0 records out

 

Real 0m2. 035 s

User 0m0. 114 s

Sys 0m1. 921 s

 

Write speed: 1000 m/2.035 = 491 m

 

[XXX] $ TIME dd If = 1gb. File BS = 64 k | dd OF =/dev/null

15625 + 0 records in

15625 + 0 records out

2000000 + 0 records in

2000000 + 0 records out

 

Real 0m2. 420 s

User 0m0. 368 s

Sys 0m1. 889 s

Read speed: 1000 m/2.420 = 413 m