Why does RHEL7 show 2 LOC interrupts per second for nohz_full cpus?

Solution Verified - Updated -

Issue

  • Why does RHEL7 show 2 LOC interrupts per second for nohz_full cpus?
[root@rhel7 ~]# taskset -c 12 sha1sum /dev/zero &
[1] 4438
[root@rhel7 ~]# perf stat -e irq_vectors:local_timer_entry -e irq_vectors:local_timer_exit -e context-switches -C 12 sleep 20

 Performance counter stats for 'CPU(s) 12':

                40      irq_vectors:local_timer_entry
                40      irq_vectors:local_timer_exit
                 0      context-switches

      20.000894842 seconds time elapsed

Environment

  • Red Hat Enterprise Linux 7.x.

Subscriber exclusive content

A Red Hat subscription provides unlimited access to our knowledgebase, tools, and much more.

Current Customers and Partners

Log in for full access

Log In

New to Red Hat?

Learn more about Red Hat subscriptions

Using a Red Hat product through a public cloud?

How to access this content