The Speed of Time
Brendan Gregg
SEPTEMBER 25, 2021
Was there some other program consuming CPU, like a misbehaving Ubuntu service that wasn't in CentOS? As a Xen guest, this profile was gathered using perf(1) and the kernel's software cpu-clock soft interrupts, not the hardware NMI. Software-based clocksources could fix those issues and provide accurate monotonically-increasing time.
Let's personalize your content