dwww Home | Manual pages | Find package

cpuwalk.bt(8)               System Manager's Manual              cpuwalk.bt(8)

NAME
       cpuwalk.bt  -  Sample  which  CPUs  are executing processes.. Uses bpf-
       trace/eBPF.

SYNOPSIS
       cpuwalk.bt

DESCRIPTION
       This tool samples CPUs at 99 Hertz, then  prints  a  histogram  showing
       which  CPUs  were  active.  99 Hertz is used to avoid lockstep sampling
       that would skew results. This tool can help identify if  your  applica-
       tion's  workload  is evenly using the CPUs, or if there is an imbalance
       problem.

       Since this uses BPF, only the root user can use this tool.

REQUIREMENTS
       CONFIG_BPF and bpftrace.

EXAMPLES
       Sample CPUs and print a summary on Ctrl-C:
              # cpuwalk.bt

FIELDS
       1st, 2nd
              The CPU is shown in the first field, after  the  "[".  Disregard
              the second field.

       3rd    A column showing the number of samples for this CPU.

       4th    This is an ASCII histogram representing the count column.

OVERHEAD
       This should be negligible.

SOURCE
       This is from bpftrace.

              https://github.com/iovisor/bpftrace

       Also  look  in  the bpftrace distribution for a companion _examples.txt
       file containing example usage, output, and commentary for this tool.

OS
       Linux

STABILITY
       Unstable - in development.

AUTHOR
       Brendan Gregg

SEE ALSO
       mpstat(1)

USER COMMANDS                     2018-09-08                     cpuwalk.bt(8)

Generated by dwww version 1.16 on Tue Dec 16 17:02:33 CET 2025.