Power Management
Battery Optimisations
Want to check how much power your laptop is consuming on battery ?
sudo powertop
It will open up and you should see something like this:
PowerTOP 2.15 Overview Idle stats Frequency stats Device stats Tunables Wake
The battery reports a discharge rate of 18.6 W
The energy consumed was 0.00 J
The estimated remaining time is 2 hours, 43 minutes
Summary: 4511.1 wakeups/second, 0.0 GPU ops/seconds, 0.0 VFS ops/sec and 128.6% CPU use
Usage Events/s Category Description
361.1 ms/s 1099.6 Process [PID 29362] yay -Qu --aur --quiet
8.6 ms/s 1103.3 Timer tick_nohz_handler
3.0 ms/s 669.7 Interrupt [17] idma64.1
190.3 ms/s 294.6 Process [PID 1474] Hyprland
1.5 ms/s 212.2 kWork engine_retire
3.0 ms/s 163.8 Interrupt [0] HI_SOFTIRQ
1.3 ms/s 139.1 kWork intel_atomic_cleanup_work
0.0 µs/s 139.1 kWork intel_atomic_commit_work
341.7 ms/s 0.00 Process [PID 29358] pacman
4.3 ms/s 128.1 Process [PID 550] [irq/95-ELAN1200]
3.1 ms/s 111.6 Interrupt [148] i915
235.8 µs/s 100.6 Timer intel_uncore_fw_release_timer
3.0 ms/s 72.3 Timer timerfd_tmrproc
0.9 ms/s 67.7 kWork __intel_wakeref_put_work
69.1 ms/s 3.7 Process [PID 29348] powertop
623.8 µs/s 24.7 Process [PID 17] [rcu_preempt]
1.0 ms/s 20.1 Process [PID 571] [irq/151-iwlwifi]
42.3 ms/s 1.8 Process [PID 29375] top
0.8 ms/s 17.4 kWork handle_update
39.6 ms/s 1.8 Process [PID 29374] top
0.9 ms/s 14.6 Process [PID 16] [ksoftirqd/0]
32.8 ms/s 0.00 Process [PID 29358] checkupdates
11.4 ms/s 5.5 Process [PID 1547] /usr/bin/gjs -m /usr/bin
61.1 µs/s 9.1 Process [PID 813] /usr/bin/asusd
4.5 ms/s 7.3 Process [PID 26549] /usr/lib/firefox/firefo
8.8 ms/s 5.5 Process [PID 15545] /usr/lib/firefox/firefo
13.8 ms/s 1.8 Process [PID 15363] alacritty
13.3 ms/s 1.8 Process [PID 15596] /usr/lib/firefox/firefo
14.5 µs/s 6.4 kWork toggle_allocation_gate
3.3 ms/s 4.6 Process [PID 15549] /usr/lib/firefox/firefo
299.3 µs/s 5.5 kWork __i915_gem_free_work
6.4 ms/s 2.7 Interrupt [7] sched(softirq)
13.1 ms/s 0.00 Process [PID 597] [kworker/u49:2]
11.9 ms/s 0.00 Process [PID 29359] checkupdates
60.0 µs/s 4.6 kWork psi_avgs_work
42.2 µs/s 4.6 kWork delayed_vfree_work
6.9 ms/s 1.8 Process [PID 15656] /usr/lib/firefox/firefox
Here you need to go in tunables. If you see bad status means linux is constantly supplying power to those pci/usb related hardwares.
It will look something like this,
Bad VM writeback timeout
Bad Enable Audio codec power management
>> Bad VM writeback timeout
Bad Enable Audio codec power management
Bad NMI watchdog should be turned off
Bad Autosuspend for USB device N-KEY Device [ASUSTeK Computer Inc.]
Bad Runtime PM for port ata1 of PCI device: Intel Corporation Cannon Lake Mobile PCH SATA AHCI Controller
Bad Runtime PM for PCI Device Realtek Semiconductor Co., Ltd. RTL8111/8168/8211/8411 PCI Express Gigabit Ethernet
Bad Runtime PM for PCI Device Intel Corporation Cannon Lake Mobile PCH SATA AHCI Controller
Bad Runtime PM for disk sda
Bad Runtime PM for PCI Device Intel Corporation HM470 Chipset LPC/eSPI Controller
Bad Runtime PM for PCI Device NVIDIA Corporation TU106M [GeForce RTX 2070 Mobile]
Bad Runtime PM for PCI Device Intel Corporation Cannon Lake PCH Shared SRAM
Bad Runtime PM for PCI Device Intel Corporation Cannon Lake PCH Thermal Controller
Bad Runtime PM for PCI Device Intel Corporation Cannon Lake PCH USB 3.1 xHCI Host Controller
Bad Runtime PM for PCI Device Intel Corporation Cannon Lake PCH CNVi WiFi
Good Bluetooth device interface status
Good Enable SATA link power management for host0
Good Runtime PM for I2C Adapter i2c-3 (i915 gmbus dpd)
The "Bad" entries in the Tunable section of powertop indicate power management features that are not enabled or optimized, which could lead to higher power consumption. You can fix these issues by enabling the relevant power-saving features.
So I fixed it by doing these commands:
To fix all these issues, I ran these commands
1. Fix VM Writeback Timeout:
VM writeback timeout controls how often dirty data in memory is written to disk. A higher timeout can save power because it reduces disk activity.
sudo bash -c 'echo 1500 > /proc/sys/vm/dirty_writeback_centisecs'\n
2. Enable Audio Codec Power Management:
Audio codecs can stay powered up even when they are not being used, wasting power. Enabling audio codec power management can save power.
sudo bash -c 'echo 1 > /sys/module/snd_hda_intel/parameters/power_save'\n
3. Turn Off NMI Watchdog:
The NMI watchdog is used for debugging purposes and can consume power. If you don't need it, it's safe to turn it off.
sudo bash -c 'echo 0 > /proc/sys/kernel/nmi_watchdog'\n
4. Enable USB Autosuspend for Devices:
To allow USB devices like your keyboard (N-KEY device) to go into low-power mode when not in use, you can enable autosuspend.
To enable autosuspend for USB devices:
for device in /sys/bus/usb/devices/*/power/control; do echo "auto" | sudo tee $device; done
5. Enable Runtime Power Management (PM) for PCI Devices:
Power management for PCI devices (such as your NVIDIA GPU, SATA controller, Ethernet controller, etc.) is currently disabled. Enabling runtime PM allows these devices to be powered down when not in use.
To enable runtime power management for PCI devices, you can use:
for device in /sys/bus/pci/devices/*/power/control; do echo "auto" | sudo tee $device; done
Alternatively, if you know the specific devices you want to target (such as the NVIDIA GPU or SATA controller), you can enable power management for individual devices. For example, to enable runtime PM for the NVIDIA GPU:
echo "auto" | sudo tee /sys/bus/pci/devices/0000:01:00.0/power/control
Replace 0000:01:00.0 with the correct PCI address for your GPU (which you can get from lspci).
6. Enable Runtime PM for Disk:
Your disk sda is not using runtime power management. Enabling power management will reduce power consumption when the disk is idle.
To enable runtime PM for the disk:
sudo bash -c 'echo "min_power" > /sys/class/scsi_host/host0/link_power_management_policy'
And finally set governor to powersaver
sudo cpupower frequency-set -g powersave
Set manual cpu frequency
sudo cpupower frequency-set -u 1.6GHz