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Questions tagged [power-management]

Systems to manage power consumption, such as system suspension and hibernation, CPU speed adjustment, disk spindown, battery usage monitoring, …

40
votes
2answers
59k views

Eject / safely remove vs umount

I'm using Ubuntu 12.04, and when I rigth click on a my flash drive icon (in the Unity left bar) I get two options that have me confused: eject and safely remove. The closer I came to an answer was ...
36
votes
3answers
75k views

How to disable USB autosuspend on kernel 3.7.10 or above?

I've updated my HTPC from kernel 3.7.10 to 3.10.7 and it seems CONFIG_USB_SUSPEND is now gone from the kernel options and included in PM. The main problem I'm facing is that I have an external HDD ...
35
votes
5answers
88k views

How to find power draw in watts? [duplicate]

I've been asked to estimate the power consumption of the servers I run for my laboratory. I thought that I'd ask if there was some handy Linux commandline to get the power consumption of the server. ...
31
votes
1answer
61k views

Setting CPU governor to on demand or conservative

I'm struggling with cpupower on ArchLinux. I want to set governor to ondemand or even to conservative. First if I do $ sudo cpupower frequency-info --governors, I only get performance powersave. So ...
29
votes
7answers
12k views

OS X: how to keep the computer from sleeping during a ssh session

When I ssh into a OS X computer on my network the session lasts until the OS X goes into sleep mode. Is there a way to prevent this from happening during my SSH session, apart from physically bumping ...
27
votes
12answers
22k views

How can I get an alert when my battery is about to die in Linux Mint?

This happens to me more than I'd like to admit, but sometimes I don't notice the power getting low since it only shows up in my status bar, then the computer just quits. I'd like a big alert that ...
26
votes
5answers
30k views

Get power consumption of a USB device

Is there a way to check how much power a USB device requires? Why do I need this? I need to connect an LTE USB stick to my Raspberry Pi, and don't know how much power it needs. We got it quite ...
26
votes
2answers
67k views

Turning off power to usb port. Or turn off power to entire usb subsystem

I have a usb lamp which I specifically bought in order to turn it off programmatically at a certain time, thus I need to remove the power to its usb port. I believe I have a usb-hub at usb6. The lamp ...
26
votes
3answers
12k views

Return value of current watt consumption on command line

Is there a way to return the current watt consumption on the command line? I have found about the powertop program, but have not seen a way to return the Watt consumption as a value to the command ...
25
votes
3answers
3k views

Why are some Intel family 6 CPU models (Core 2, Pentium M) not supported by intel_idle?

I've been tuning my Linux kernel for Intel Core 2 Quad (Yorkfield) processors, and I noticed the following messages from dmesg: [ 0.019526] cpuidle: using governor menu [ 0.531691] clocksource: ...
23
votes
5answers
9k views

How do I make my laptop sleep when it reaches some low battery threshold?

I'm using Ubuntu, but I have i3 as my window manager instead of a desktop environment. When my battery reaches 0%, the computer will just abruptly shut down, no warning or anything. Is there a ...
20
votes
5answers
44k views

How to turn off Wireless power management permanently

In Linux Mint 17.3 / 18 iwconfig says the power management of my wireless card is turned on. I want to turn it off permanently or some workaround on this issue. sudo iwconfig wlan0 power off works, ...
17
votes
3answers
57k views

How to Reset/Cycle Power to a PCIe Device?

I have a PCIe device that only works correctly when the computer is fully powered off then on again. Issuing a simple reboot or reboot -p command does not appear to cycle the power to the PCIe card, ...
16
votes
1answer
2k views

Monitor connected via displayport to DVI adapter won't sleep properly

I have a monitor connected to my machine that displays odd behavior when entering power saving sleep mode. When entering sleep, the monitor will alternate between blanking and displaying a default ...
15
votes
8answers
19k views

Gnome 3: how to set power button to shutdown instead of suspend?

I am using GNOME 3.18.1 on Arch Linux 4.2.5-1-ARCH x86_64 on a Dell E6530 laptop. Since I installed this OS years ago, the power button on my laptop has always led my OS to completely power down. ...
15
votes
4answers
44k views

Ubuntu Server Continuously “goes to sleep”

I am running a web server at home using Ubuntu 11.4 (maybe? I can't 100% recall) on an older AMD 2400+ desktop with 1 or 2 GB of RAM. Sorry I can't recall the details 100%. Anyway, I have a KVM ...
15
votes
3answers
9k views

upowerd consuming 100% cpu

upowerd is consuming nearly 100% of CPU. I am currently affected by this issue on both a Lenovo Thinkpad E520 and on a desktop PC running Core i7 and Asus Z170a motherboard. Both run Kubuntu 15.10. ...
13
votes
2answers
23k views

How to get current CPUPower governor

I want to get the current CPUPower governor. When I type cpupower frequency-info I get a lot of information. I just want to get the governor, just like "ondemand" with no more information, to use its ...
13
votes
3answers
14k views

Shutdown my (backup) hard disk on Linux when I don't use it

I have a hard disk in my computer that I use to make backups of my data. I do not use this disk otherwise. How can I stop this disk from spinning once my backup is finished? Also how would I make it ...
13
votes
7answers
16k views

Screen turns on automatically (xset dpms force off)

I am using xset dpms force off to manually turn my screen off to save power. However, it turns back on after some time (20 - 40 seconds). Distro: Ubuntu-Lucid Graphics: Intel 4500 MHD Trying ...
13
votes
5answers
7k views

How to stop the screen from blanking / blacking out?

I have re-installed Debian 7 (Wheezy) after a while. For the first time, I am using the open-free Nvidia drivers (not nouveau) and vesafb for virtual consoles. I cannot, for the life of me, stop the ...
13
votes
1answer
877 views

Disks (in usb enclosure) keep waking up even when not mounted

Setup I have USB enclosure (Buffalo DriveStation Quad) containing four drives connected to my nas server (ubuntu server 14.04). The enclosure is configured to JBOD mode, so I'll see all the disks in ...
12
votes
2answers
1k views

Screen brightness reverts to max after returning from `xset dpms` display suspend

I'm running the openbox window manager and using this line in my autostart.sh to control display power management: xset dpms 0 60 0 This works nicely, causing the display to suspend after 60 seconds ...
11
votes
3answers
7k views

How can I set power button (on computer case) to power off system with `systemd`?

How can I set the power button (on my computer case, not keyboard) to power off the system with systemd (without acpid)?
11
votes
2answers
22k views

How to adjust charging thresholds of laptop battery?

My laptop is Lenovo T400, and OS is Ubuntu 12.04. I have not been able to adjust the thresholds for battery starting charging and stopping charging. I observed that its current starting charging ...
11
votes
4answers
5k views

NetworkManager: disabled network when sending system to sleep

When I suspend my notebook, NetworkManager disables the wireless network (in nm-manager.c:do_sleep_wake). However, I'd love to still use the network for a very short time (to unmount cifs mounts, ...
11
votes
1answer
2k views

Lenovo T440s battery status unknown, but charging?

I'm trying to configure my Lenovo on arch linux. The last thing I need to do is get the battery 100% working. Right now it appears that the main battery's state is unknown: ...
10
votes
5answers
11k views

How can I run an hdparm command after boot and resume on Fedora 19?

I bought a new HD(WD5000BPVT) which unfortunately tries to sleep every 5-8 seconds. Not only is the clicking noise quite audible, the 1-second spinup time adds very noticeable latency in day-to-day ...
10
votes
3answers
8k views

How do I make Powertop's suggestions permanent?

When I run Powertop, and look at the Tunables screen, about twenty things are listed as Bad. I can toggle these to Good by pressing enter, and when I do so, projected battery lifetime doubles. How ...
10
votes
1answer
11k views

Why does drive not enter standby mode when using hdparm -S

When reading the hdparm manual pages, it says that the -S value is used by the drive to determine how long to wait (with no disk activity) before turning off the spindle motor to save power ...
10
votes
1answer
1k views

How to prevent the Linux kernel from waking a secondary HDD from sleep

Is there a way to instruct the (Linux) kernel not to wake up a secondary hdd after a system sleep/wake-up cycle? I'm asking because in my laptop I have an SSD as a primary drive containing the system ...
10
votes
1answer
458 views

Screen doesn't always shut off on its own

It seems like when I have certain web pages focused, my screensaver will kick in, but the screen won't turn itself off. Does anyone have any ideas why this might be? Is there a way to disable whatever ...
10
votes
1answer
845 views

ACPI group/action undefined: processor / LNXCPU

If I unplug my laptop from the AC adapter, I will get ACPI errors like these: May 07 21:45:04 veritas root[7067]: ACPI group/action undefined: processor / LNXCPU:00 May 07 21:45:04 veritas root[7076]:...
9
votes
2answers
10k views

Powertop tunables: what does it do?

I just installed Powertop 1.98 on my laptop (T420 + FC15). There is a section called "Tunables". Half of my devices show as Bad. I see I can toggle from Bad to Good? What this section is for? What ...
9
votes
2answers
913 views

System-wide power management policy on debian-based distros?

I would like to put idle machines in our lab (running Mint Debian edition) on standby after a timeout. I have tried pm-suspend and it puts the machines on standby and wakes up fine. Does anybody know ...
8
votes
5answers
2k views

How to poweroff when there's no systemd/init (e.g. using init=/bin/bash)?

poweroff complains that it can't connect to systemd via DBus (of course, it's not alive). I did sync followed by kill $$, thinking that pid 1 dying would cue the kernel to poweroff, but that caused a ...
8
votes
2answers
4k views

How to prevent my screens from dimming (going black) from the command line

In KDE, there was a system setting where you could specifically set the monitors to never go black. Now I've switched to dwm and (it might not be related) my screens dim after about 10 minutes. How ...
8
votes
3answers
1k views

How can I find out the estimated power use of my desktop computer?

Is there a way to get the computer power usage instead of battery load tracking (what for instance seemingly powertop does), which is obviously not too useful on desktops?
8
votes
3answers
2k views

Will switching from Gnome to LXDE improve battery life?

I currently have Fedora 14 and the battery life is not so good. I am planning to switch to Fedora 16. Will I get significantly more battery life if I go for the LXDE spin instead of GNOME?
8
votes
3answers
8k views

How to find reason a notebook wakes up?

I'm having a problem with my notebook suspending, but then waking up when I don't want it to (either immediately, or much later when in the bag - I may have two issues to solve here). But for the ...
8
votes
1answer
1k views

Is it possible to automatically wake from suspend?

Here's my problem: I have a laptop running Arch that I just keep on at home. It's got a good 4 hour battery life, but sometimes my daughter is playing near where it's kept and ends out pulling the ...
8
votes
2answers
3k views

Hard disk not going to standby automatically

I have a hard drive, which should go to standby automatically after 30 or 60 minutes. I tried (3 minutes for testing): # hdparm -S 36 /dev/sda /dev/sda: setting standby to 36 (3 minutes) And it ...
8
votes
1answer
1k views

How can I send power on/off signals to a VGA monitor?

I've used some old spare parts to make a sort-of kiosk for my kitchen. It's running OpenBSD and has a simple text based UI (no X Server). I plan to add an Arduino with a motion sensor that ...
8
votes
2answers
16k views

How to avoid powering down certain USB devices when a machine is suspended

I'd like to maintain power supply to a USB-powered drive when the system goes into suspend (AKA S3 or "suspend-to-RAM") mode. Normally the power is cut while the machine is suspended, which causes it ...
8
votes
1answer
413 views

Power saving enables touchpad

I've installed power saving packages (bumblebee, laptop-mode-tools, and cpufreq) to my laptop with Debian Wheezy. Thanks to that I decrease power usage from 32W to 10W. But now I faced the issue that ...
8
votes
2answers
698 views

Linux kernel 3.3 power regression

I am using Fedora 16 in my DELL n4110. I recently upgraded the kernel from 3.2 to 3.3. In contradiction to the official claim, my system still drains battery as hell. It only provides 1:30 to 2 hrs of ...
8
votes
0answers
2k views

DPMS does not work: the monitor is not switched off [closed]

I have a monitor which was properly switched off by my Debian PC when unused. I attached it to another machine and, this times, it is never switched off. In /etc/X11/xorg.conf, I have: Section "...
7
votes
2answers
4k views

Determine status of laptop lid

I have a weird problem where my laptop will wake when it's closed, generating a lot of heat and causing much frustration. Is there a way that I can tell if the laptop's lid is closed so that I can ...
7
votes
2answers
2k views

Do I need acpid in a virtual machine?

I'm always wondering if power management facilities in a virtual machine is necessary? i.e acpid. And I'm not sure if they still function in a virtual machine.
7
votes
3answers
3k views

How do I prevent GNOME suspending while I finish a compilation job

I am trying to build a custom kernel for my machine which is taking a long time to build (as expected). Is it possible to stop my GNOME desktop from suspending the machine until the compilation has ...