console screen does not go into power saving mode

[Benni.blanko]

Hi there,
I installed Truenas 12U6 and U7 on two HP DL380 Gen.9 servers; working very good so far.
But I noticed, that the console screen/monitors stays on all the time.
Other Linuxes switch the console screen off after some minutes of inactivity. Allowing the monitor to go into standby mode (to save energy and avoid burn in of static texts).
Can Truenas do this as well? What settings do I have to modify?

Thanks in Advance
Benni

 

[jgreco]

Desktop versions of Linux may do this. Usually the server versions do not, because servers are not expected to have a monitor on them 24/7, and crash results and all that aren't useful if the screen isn't enabled.

I believe the authors of the vt console driver expected that non-graphical desktop use was an edge case, and that if you had a text mode terminal, it was expected to be a server. As far as I know, vt doesn't have the old sc screensaver capabilities, because they expect X11 to provide screensaving modes for desktop users.

 

[Benni.blanko]

So this behavior is "working as designed" and occurs on (all) other installations as well?

I'm not looking for a fancy screen saver but a simple "put screen in energy saving mode" = switch it off.

 

[jgreco]

So this behavior is "working as designed" and occurs on (all) other installations as well?

I'm not looking for a fancy screen saver but a simple "put screen in energy saving mode" = switch it off.

The mechanics of detecting idleness and running some code of some sort are the same; whether you're drawing an ASCII art beastie on the screen or signaling the monitor to turn off is just cosmetic.

 

[Benni.blanko]

But who want's to draw ASCII art?
It's to save energy (let the monitor go to standby) and avoid burn-in of static texts.

 

[jgreco]

But who want's to draw ASCII art?
It's to save energy (let the monitor go to standby)

That's your opinion. I've seen lots of servers over the years with a permanent assigned monitor, sometimes wired to the lights in the room, sometimes wired to a KVM, which in both cases you have reasons you don't want the server's VGA output to go into standby. If I wanted to save energy, I'd turn off all the gear and send everyone home for the day.

and avoid burn-in of static texts.

THAT'S the goal. Literally all of the sc based screensavers accomplish that goal. Only one switches the monitor to powersave, of course, because two that switch the monitor to powersave would be one more than needed. I am a lifelong fan of star_saver.ko. It's inoffensive, yet offers easy and obvious evidence as to whether the kernel has wedged or not.

I am still a bit incensed at the vt driver for not having feature parity with sc.