Help with powertop idle state output
Help with powertop idle state output
On a small form factor PC with an i5-9500, Debian 12, 6.2.16 kernel, running Proxmox, powertop
shows the following idle stats:
PowerTOP 2.14 Overview Idle stats Frequency stats Device stats Tunables WakeUp Pkg(HW) | Core(HW) | CPU(OS) 0 | | C0 active 2.8% | | POLL 0.0% 0.0 ms | | C1 1.1% 0.4 ms C2 (pc2) 7.2% | | C3 (pc3) 5.5% | C3 (cc3) 0.0% | C3 0.1% 0.1 ms C6 (pc6) 1.5% | C6 (cc6) 1.9% | C6 2.2% 0.6 ms C7 (pc7) 75.2% | C7 (cc7) 92.8% | C7s 0.0% 0.0 ms C8 (pc8) 0.0% | | C8 21.5% 2.5 ms C9 (pc9) 0.0% | | C9 0.0% 0.0 ms C10 (pc10) 0.0% | | | | C10 72.8% 12.5 ms | | C1E 0.4% 0.2 ms | Core(HW) | CPU(OS) 1 | | C0 active 1.4% | | POLL 0.0% 0.0 ms | | C1 0.7% 0.9 ms | | | C3 (cc3) 0.1% | C3 0.1% 0.2 ms | C6 (cc6) 1.0% | C6 1.1% 0.8 ms | C7 (cc7) 96.3% | C7s 0.0% 0.0 ms | | C8 18.9% 2.9 ms | | C9 0.0% 0.0 ms | | | | C10 78.3% 24.8 ms | | C1E 0.0% 0.0 ms ...
On a custom-built server with an i5-13500, Asus Pro WS W680M-ACE SE motherboard, Unraid (which uses Slackware), 6.1.38 kernel, it shows the following output:
PowerTOP 2.15 Overview Idle stats Frequency stats Device stats Tunables WakeUp Pkg(HW) | Core(HW) | CPU(OS) 0 CPU(OS) 1 | | C0 active 5.9% 0.9% | | POLL 0.1% 0.0 ms 0.0% 0.0 ms | | C1_ACPI 14.2% 0.2 ms 1.0% 0.1 ms C2 (pc2) 0.0% | | C2_ACPI 39.2% 0.8 ms 27.0% 0.9 ms C3 (pc3) 0.0% | C3 (cc3) 0.0% | C3_ACPI 33.6% 1.2 ms 69.7% 3.0 ms C6 (pc6) 0.0% | C6 (cc6) 1.1% | C7 (pc7) 0.0% | C7 (cc7) 0.0% | C8 (pc8) 0.0% | | C9 (pc9) 0.0% | | C10 (pc10) 0.0% | | | Core(HW) | CPU(OS) 2 CPU(OS) 3 | | C0 active 10.4% 0.5% | | POLL 0.0% 0.0 ms 0.0% 0.0 ms | | C1_ACPI 17.4% 0.2 ms 0.4% 0.2 ms | | C2_ACPI 14.3% 0.8 ms 4.9% 0.6 ms | C3 (cc3) 0.0% | C3_ACPI 41.8% 5.4 ms 93.5% 5.5 ms | C6 (cc6) 5.9% | | C7 (cc7) 26.7% | | | | | | | | Core(HW) | CPU(OS) 4 CPU(OS) 5 | | C0 active 11.7% 0.2% | | POLL 0.0% 0.1 ms 0.0% 0.0 ms | | C1_ACPI 19.0% 0.1 ms 0.0% 0.0 ms | | C2_ACPI 11.3% 0.7 ms 0.0% 0.0 ms | C3 (cc3) 0.0% | C3_ACPI 39.6% 7.7 ms 99.6% 7.0 ms | C6 (cc6) 1.3% | | C7 (cc7) 25.4% | ...
Both systems have C-states enabled in the BIOS.
I have a few questions I'm hoping someone can help with:
- Why does the older system show more C-states in the right-most "CPU(OS)" column?
- What does it mean when they're suffixed with "_ACPI" like in the output from the new system?
- How do I debug the new system not hitting any CPU package C-states?
I can't find any documentation about this, neither on the man page nor on Intel's site (the official powertop URL https://01.org/powertop doesn't go anywhere useful any more).
Thanks!