rtcwake
The command that you are interested in is rtcwake
:
This program is used to enter a system sleep state until specified wakeup time.
testing
To find the correct syntax that works for you try the following:
sudo rtcwake -u -s 60 -m mem
This should suspend the computer for 60 seconds before restoring. The significant parameter is mem
You have several options you can choose - play to find the value that works best for you:
standby
ACPI state S1. This state offers minimal, though real,
power savings, while providing a very low-latency transi‐
tion back to a working system. This is the default mode.
mem ACPI state S3 (Suspend-to-RAM). This state offers signif‐
icant power savings as everything in the system is put
into a low-power state, except for memory, which is
placed in self-refresh mode to retain its contents.
disk ACPI state S4 (Suspend-to-disk). This state offers the
greatest power savings, and can be used even in the
absence of low-level platform support for power manage‐
ment. This state operates similarly to Suspend-to-RAM,
but includes a final step of writing memory contents to
disk.
off ACPI state S5 (Poweroff). This is done by calling
'/sbin/shutdown'. Not officially supported by ACPI, but
usually working.
no Don't suspend. The rtcwake command sets RTC wakeup time
only.
on Don't suspend, but read RTC device until alarm time
appears. This mode is useful for debugging.
suspend until a known time
A script (at the bottom of this post) could be used to suspend your computer and wake at a specific time:
syntax is suspend_until [hh:mm]
for example
sudo ./suspend_until 07:30
Save the script as the name suspend_until
and give it execute rights i.e.
chmod +x suspend_until
Cron
You can create a root cron job that calls this script to execute at a specific time in the evening and then awake in the morning:
sudo crontab -e
Now enter something like to run the suspend script at 23:30:
30 23 * * * /home/myhomefolder/suspend_until 07:30
suspend_until script
#!/bin/bash
# Auto suspend and wake-up script
#
# Puts the computer on standby and automatically wakes it up at specified time
#
# Written by Romke van der Meulen <redge.online@gmail.com>
# Minor mods fossfreedom for AskUbuntu
#
# Takes a 24hour time HH:MM as its argument
# Example:
# suspend_until 9:30
# suspend_until 18:45
# ------------------------------------------------------
# Argument check
if [ $# -lt 1 ]; then
echo "Usage: suspend_until HH:MM"
exit
fi
# Check whether specified time today or tomorrow
DESIRED=$((`date +%s -d "$1"`))
NOW=$((`date +%s`))
if [ $DESIRED -lt $NOW ]; then
DESIRED=$((`date +%s -d "$1"` + 24*60*60))
fi
# Kill rtcwake if already running
sudo killall rtcwake
# Set RTC wakeup time
# N.B. change "mem" for the suspend option
# find this by "man rtcwake"
sudo rtcwake -l -m mem -t $DESIRED &
# feedback
echo "Suspending..."
# give rtcwake some time to make its stuff
sleep 2
# then suspend
# N.B. dont usually require this bit
#sudo pm-suspend
# Any commands you want to launch after wakeup can be placed here
# Remember: sudo may have expired by now
# Wake up with monitor enabled N.B. change "on" for "off" if
# you want the monitor to be disabled on wake
xset dpms force on
# and a fresh console
clear
echo "Good morning!"
N.B.
Change mem
in this part of the script for whatever suspend method works for you:
# Set RTC wakeup time
sudo rtcwake -l -m mem -t $DESIRED &
You may also have to substitute the -u
flag in place of the -l
flag depending on whether your hardware clock uses UTC (-u
) or local (-l
) time. Note that your hardware clock is different from the system clock you see in your operating system.
credit to redgeonline
Best Answer
You can do (at least half of) this with Gnome Schedule. (
sudo apt-get install gnome-schedule
) (NB: it gets put in your launcher as Scheduled Tasks, though typing gnome-schedule still brings it up.)After launching it, "New" -> "Recurrent Task". Fill in the form as you see fit.
The command to hibernate is
/usr/sbin/pm-hibernate
(Suspend is/usr/sbin/pm-suspend
)In regards to waking up again, please see "How do I schedule waking up from hibernation?"
Alternately, you can install the "power management interface". (
sudo apt-get install powermanagement-interface
)Then create a script like this:
And schedule it in the root's crontab.
Source