xscreensaver power management

[Marco Moock]

Hello!

If I want to enable xscreensaver to turn off the monitor, it doesn't
work. If I select the option, it will be unselected when I start
xscreensaver-settings again.

Is there some package missing on my system or is this feature
unsupported on Slackware?

[John McCue]

Post by Marco Moock
Hello!
If I want to enable xscreensaver to turn off the monitor, it doesn't
work. If I select the option, it will be unselected when I start
xscreensaver-settings again.

Did not know it could do that. But I looked at
xscreensaver-settings and I see power management,
interesting.

Post by Marco Moock
Is there some package missing on my system or is this feature
unsupported on Slackware?

I do not know, but I thought monitor power management was
a BIOS option as opposed to xscreensaver. Or maybe the
BIOS setting for power-down is disabled.

[Marco Moock]

Post by John McCue

Post by Marco Moock
Hello!
If I want to enable xscreensaver to turn off the monitor, it doesn't
work. If I select the option, it will be unselected when I start
xscreensaver-settings again.

Did not know it could do that. But I looked at
xscreensaver-settings and I see power management,
interesting.

Post by Marco Moock
Is there some package missing on my system or is this feature
unsupported on Slackware?

I do not know, but I thought monitor power management was
a BIOS option as opposed to xscreensaver. Or maybe the
BIOS setting for power-down is disabled.

Monitor can be turned off by the system via GPU.
https://en.wikipedia.org/wiki/VESA_Display_Power_Management_Signaling

I dunno if that protocol is also being used for integrated LVDS laptop
displays.

[Rich]

Post by Marco Moock

Post by John McCue

Post by Marco Moock
Hello!
If I want to enable xscreensaver to turn off the monitor, it doesn't
work. If I select the option, it will be unselected when I start
xscreensaver-settings again.

Did not know it could do that. But I looked at
xscreensaver-settings and I see power management,
interesting.

Post by Marco Moock
Is there some package missing on my system or is this feature
unsupported on Slackware?

I do not know, but I thought monitor power management was
a BIOS option as opposed to xscreensaver. Or maybe the
BIOS setting for power-down is disabled.

Monitor can be turned off by the system via GPU.
https://en.wikipedia.org/wiki/VESA_Display_Power_Management_Signaling
I dunno if that protocol is also being used for integrated LVDS laptop
displays.

In my admitedly small sample size, all the laptop's I've run Linux on
have supported DPMS powerdown for the LCD panel.

"xset dpms force off" and the panel turns off.

[Marco Moock]

Post by Rich
"xset dpms force off" and the panel turns off.

That works, so DPMS itself is possible.

The questions is now why screensaver can't handle that.

[Rich]

Post by Marco Moock

Post by Rich
"xset dpms force off" and the panel turns off.

That works, so DPMS itself is possible.
The questions is now why screensaver can't handle that.

If you mean "why does the screen not power down with xscreensaver" --
then the reason might just be that "screen savers" are a legacy from
the CRT days intended to prevent phosphor burn in by displaying a
moving/changing image when the system is idle (and predating the days
of DPMS powerdown control). They were originally meant to draw
animations, not simply power down the screen.

Do note that xscreensaver's man page claims it has support for
triggering powerdown, but you do have to configure it to do so (see the
section "Power Management" in the xscreensaver man page).

But, if the only reason you run xscreensaver is for idle power down,
then that is silly, as X already supports idle time-out power down
natively, so xscreensaver is not needed for that singlar purpose.

If, however, you are also using the "screen locking" feature of
xscreensaver, then you do need to run it to get the screen locking
feature -- and for powerdown you'll need to tell it to perform power
off as well (or configure X to power down a short time after the idle
lock engages).

[John McCue]

Post by Rich

Post by Marco Moock

Post by Rich
"xset dpms force off" and the panel turns off.

That works, so DPMS itself is possible.
The questions is now why screensaver can't handle that.

<snip>

Post by Rich
But, if the only reason you run xscreensaver is for idle power down,

I wonder if Marco is running an animation ?
I have "Mode" set to "Blank Screen Only" in
xscreensaver-settings. Maybe animations prevent
X or xscreensaver from powering down the monitor.

<snip>

[Marco Moock]

Post by John McCue
I wonder if Marco is running an animation ?

No, and I don't want.

Post by John McCue
I have "Mode" set to "Blank Screen Only" in
xscreensaver-settings.

Me too.

Post by John McCue
Maybe animations prevent X or xscreensaver from powering down the
monitor.

IIRC this can be set, e.g. to run an animation for a specific amount of
time and then turning the screen off.

[Marco Moock]

Post by Rich
But, if the only reason you run xscreensaver is for idle power down,
then that is silly, as X already supports idle time-out power down
natively, so xscreensaver is not needed for that singlar purpose.
If, however, you are also using the "screen locking" feature of
xscreensaver, then you do need to run it to get the screen locking
feature -- and for powerdown you'll need to tell it to perform power
off as well (or configure X to power down a short time after the idle
lock engages).

That is my intended use. I want to for locking after some idle time,
locking manually and for turning the monitor off after some time to
avoid wasting power.

The latter doesn't work, if I select the option it will be unselected
at next start of xscreensaver-settings.

[Rich]

Post by Marco Moock

Post by Rich
But, if the only reason you run xscreensaver is for idle power down,
then that is silly, as X already supports idle time-out power down
natively, so xscreensaver is not needed for that singlar purpose.
If, however, you are also using the "screen locking" feature of
xscreensaver, then you do need to run it to get the screen locking
feature -- and for powerdown you'll need to tell it to perform power
off as well (or configure X to power down a short time after the idle
lock engages).

That is my intended use. I want to for locking after some idle time,
locking manually and for turning the monitor off after some time to
avoid wasting power.

Ok, then the basic native provision in X, while meeting your "save
power" requirement, won't meet the 'lock screen' requirement.

Post by Marco Moock
The latter doesn't work, if I select the option it will be unselected
at next start of xscreensaver-settings.

Hmm, no idea why there. Checking the man page, it says it saves the
settings in ~/.xscreensaver. On my Slack 15 system, toggling the
"powerdown" option changes this line in that file (between "True" and
"False" states):

dpmsEnabled: False

And the settings persist across exits.

Do you possibly have ~/.xscreensaver file that is set to be read only
(or labeled 'immutable')?

Or are you running the settings program as a different user than the
user under which the daemon is running?

[Javier]

Post by Rich
If, however, you are also using the "screen locking" feature of
xscreensaver, then you do need to run it to get the screen locking
feature -- and for powerdown you'll need to tell it to perform power
off as well (or configure X to power down a short time after the idle
lock engages).

For just locking the screen xlockmore is simpler and has less
dependencies than xscreensaver.

https://www.sillycycle.com/xlxs.html

You can even compile a blank only screen minimalistic version of it:

./configure --prefix=/usr --disable-setuid \
--enable-appdefaultdir=/usr/share/X11/app-defaults \
--enable-pam --without-esound --without-ftgl \
--without-motif --without-magick --without-rplay \
--without-gtk --without-gtk2 --enable-blank-only

[Rich]

Post by Marco Moock
Hello!
If I want to enable xscreensaver to turn off the monitor, it doesn't
work. If I select the option, it will be unselected when I start
xscreensaver-settings again.
Is there some package missing on my system or is this feature
unsupported on Slackware?

No, monitor power down is supported by X11 itself. You don't need
xscreensaver for a power down state.

Look at the DPMS options for the 'xset' command. Of course, your
monitor needs to recognize and perform the right thing when X tells it
to power down. Most monitors do, but YMMV depending on exactly what
you have.

[Marco Moock]

Post by Rich
No, monitor power down is supported by X11 itself. You don't need
xscreensaver for a power down state.

Aren't they invoked by xscreensaver?

[Rich]

Post by Marco Moock

Post by Rich
No, monitor power down is supported by X11 itself. You don't need
xscreensaver for a power down state.

Aren't they invoked by xscreensaver?

Maybe - but they don't need to be. X already natively supports lack of
usage timeout for screen turn off.

All you get is "blank" and "turn off" -- no fancy GL pipes or flying
toaster images bouncing around your display. But it is all built in.

Look at the manpage for xset, the DPMS options provide for the 'power
down monitor after timeout' features.