How do I get CPU Clock Speed in C++ (Linux)?

Question

How can I get the CPU clock speed in C++?

I am running Ubuntu 9.10 if that makes any difference.

score 7 · Accepted Answer · answered Mar 10 '10 at 17:14

7

Read the pseudo-file /proc/cpuinfo. See this link for an explanation of the fields it contains.

answered Mar 10 '10 at 17:14

3

This is not the current CPU speed however. Or not always. – Zan Lynx Mar 10 '10 at 17:17
There are new links. For RHEL 4, the explanation is in the [Reference Guide](https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/4/html/Reference_Guide/s2-proc-cpuinfo.html). For RHEL 6, the explanation is in the [Deployment Guide](https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/6/html/Deployment_Guide/s2-proc-cpuinfo.html) – Jaime Sep 16 '17 at 17:01

score 2 · Answer 2 · answered Mar 10 '10 at 17:27

2

This information is available in sysfs. In particular, check out scaling_cur_freq and cpuinfo_cur_freq in /sys/devices/system/cpu/cpu*/cpufreq.

answered Mar 10 '10 at 17:27

David

score 1 · Answer 3 · answered Mar 10 '10 at 17:29

1

When I had a Compaq Athlon64 laptop, its /proc/cpuinfo always reported its maximum speed.

I only got reliable current frequency numbers from the files in /sys/devices/system/cpu/*/cpufreq.

I suppose your mileage may vary.

answered Mar 10 '10 at 17:29

Zan Lynx

score 1 · Answer 4 · answered Mar 11 '10 at 05:38

1

try executing the command lscpu

answered Mar 11 '10 at 05:38

BlueSilver

4 Answers4