n...@holland-consulting.net (Nick Holland), 2014.10.25 (Sat) 06:08 (CEST):
[big snip of the original discussion on screen blanking and it's
handling by mplayer]
> Personally, I'm slowly losing interest in screen blanking. LCD screens
> draw little power when on, [...]
[snipping again]
> A laptop plugged into the wall...why power down the screen at all? A
> laptop running on batteries...if you aren't going to use it, why not
> just suspend it?
When I read this I thought that there was some room between "not using"
and "justifies suspend". (It only took two months until I got going...)
For quick power saving, stand-by would do. It takes 2 seconds to go to
stand-by, 7 seconds to resume (dmesg below).
This is fast enough for intentional breaks, I think.
But with me sitting in front of the machine, what happens by far more
often are unintentional breaks, i.e. me staring and thinking (or not),
or me trying to get work done but being interrupted, leaving the machine
in a hurry.
Time driven automagic (xidle(1)) stand-by would be too much for these
cases, there may be tasks running that I want to continue.
But screen blanking/unpowering? This cannot hurt, but does it help
to save power? (Not only for working longer but also for the
environment...)
All numbers taken on a lenovo X200s (dmesg follows) with batteries
removed, a cheapish power meter and only default deamons running (and
doing nothing). What might matter and isn't easy to see/not visible in
the dmesg, my sd0 (MKNSSDCR120GB) is an SSD with atactl(8) smartenable,
writecacheenable, acousticset 126, apmset 126.
1.1 W stand-by - apm -S
12.5 W display off - xrandr --output LVDS1 --off
15 W display 10% - xbacklight -set 10
20 W display 100% - xbacklight -set 100
So in the range between 1.1 W (minimum idle power consumption) and 20 W
(maximum idle power consumption), turning the screen off automagically
saves me eight Watts out of 19 that could be saved (if I had left
intentionally and used stand-by). Almost half of the maximum power
saving achieved by unpowering the screen if leaving in a hurry is good
enough for me.
Bye, Marcus
OpenBSD 5.6-current (GENERIC.MP) #414: Sun Oct 12 16:02:44 MDT 2014
dera...@amd64.openbsd.org:/usr/src/sys/arch/amd64/compile/GENERIC.MP
real mem = 4168814592 (3975MB)
avail mem = 4049133568 (3861MB)
mpath0 at root
scsibus0 at mpath0: 256 targets
mainbus0 at root
bios0 at mainbus0: SMBIOS rev. 2.4 @ 0xe0010 (68 entries)
bios0: vendor LENOVO version "6DET72WW (3.22 )" date 10/25/2012
bios0: LENOVO 7470W1W
acpi0 at bios0: rev 2
acpi0: sleep states S0 S3 S4 S5
acpi0: tables DSDT FACP SSDT ECDT APIC MCFG HPET SLIC BOOT ASF! SSDT TCPA SSDT
SSDT SSDT
acpi0: wakeup devices LID_(S3) SLPB(S3) IGBE(S4) EXP0(S4) EXP1(S4) EXP2(S4)
EXP3(S4) USB0(S3) USB3(S3) USB5(S3) EHC0(S3) EHC1(S3) HDEF(S4)
acpitimer0 at acpi0: 3579545 Hz, 24 bits
acpiec0 at acpi0
acpimadt0 at acpi0 addr 0xfee00000: PC-AT compat
cpu0 at mainbus0: apid 0 (boot processor)
cpu0: Intel(R) Core(TM)2 Duo CPU L9400 @ 1.86GHz, 798.12 MHz
cpu0:
FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CFLUSH,DS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,PBE,SSE3,DTES64,MWAIT,DS-CPL,VMX,SMX,EST,TM2,SSSE3,CX16,xTPR,PDCM,SSE4.1,XSAVE,NXE,LONG,LAHF,PERF
cpu0: 6MB 64b/line 16-way L2 cache
cpu0: smt 0, core 0, package 0
mtrr: Pentium Pro MTRR support, 7 var ranges, 88 fixed ranges
cpu0: apic clock running at 266MHz
cpu1 at mainbus0: apid 1 (application processor)
cpu1: Intel(R) Core(TM)2 Duo CPU L9400 @ 1.86GHz, 798.01 MHz
cpu1:
FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CFLUSH,DS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,PBE,SSE3,DTES64,MWAIT,DS-CPL,VMX,SMX,EST,TM2,SSSE3,CX16,xTPR,PDCM,SSE4.1,XSAVE,NXE,LONG,LAHF,PERF
cpu1: 6MB 64b/line 16-way L2 cache
cpu1: smt 0, core 1, package 0
ioapic0 at mainbus0: apid 1 pa 0xfec00000, version 20, 24 pins
ioapic0: misconfigured as apic 2, remapped to apid 1
acpimcfg0 at acpi0 addr 0xe0000000, bus 0-63
acpihpet0 at acpi0: 14318179 Hz
acpiprt0 at acpi0: bus 0 (PCI0)
acpiprt1 at acpi0: bus -1 (AGP_)
acpiprt2 at acpi0: bus 2 (EXP0)
acpiprt3 at acpi0: bus 3 (EXP1)
acpiprt4 at acpi0: bus -1 (EXP2)
acpiprt5 at acpi0: bus 5 (EXP3)
acpicpu0 at acpi0: C3, C2, C1, PSS
acpicpu1 at acpi0: C3, C2, C1, PSS
acpipwrres0 at acpi0: PUBS, resource for USB0, USB3, USB5, EHC0, EHC1
acpitz0 at acpi0: critical temperature is 127 degC
acpitz1 at acpi0: critical temperature is 104 degC
acpibtn0 at acpi0: LID_
acpibtn1 at acpi0: SLPB
acpibat0 at acpi0: BAT0 not present
acpibat1 at acpi0: BAT1 not present
acpiac0 at acpi0: AC unit online
acpithinkpad0 at acpi0
acpidock0 at acpi0: GDCK not docked (0)
cpu0: Enhanced SpeedStep 798 MHz: speeds: 1867, 1866, 1600, 800 MHz
pci0 at mainbus0 bus 0
pchb0 at pci0 dev 0 function 0 "Intel GM45 Host" rev 0x07
vga1 at pci0 dev 2 function 0 "Intel GM45 Video" rev 0x07
intagp0 at vga1
agp0 at intagp0: aperture at 0xd0000000, size 0x10000000
inteldrm0 at vga1
drm0 at inteldrm0
inteldrm0: 1280x800
wsdisplay0 at vga1 mux 1: console (std, vt100 emulation)
wsdisplay0: screen 1-5 added (std, vt100 emulation)
"Intel GM45 Video" rev 0x07 at pci0 dev 2 function 1 not configured
"Intel GM45 HECI" rev 0x07 at pci0 dev 3 function 0 not configured
puc0 at pci0 dev 3 function 3 "Intel GM45 KT" rev 0x07: ports: 1 com
com4 at puc0 port 0 apic 1 int 17: ns16550a, 16 byte fifo
com4: probed fifo depth: 15 bytes
em0 at pci0 dev 25 function 0 "Intel ICH9 IGP M AMT" rev 0x03: msi, address
00:1f:16:32:df:5c
uhci0 at pci0 dev 26 function 0 "Intel 82801I USB" rev 0x03: apic 1 int 20
uhci1 at pci0 dev 26 function 1 "Intel 82801I USB" rev 0x03: apic 1 int 21
uhci2 at pci0 dev 26 function 2 "Intel 82801I USB" rev 0x03: apic 1 int 22
ehci0 at pci0 dev 26 function 7 "Intel 82801I USB" rev 0x03: apic 1 int 23
usb0 at ehci0: USB revision 2.0
uhub0 at usb0 "Intel EHCI root hub" rev 2.00/1.00 addr 1
azalia0 at pci0 dev 27 function 0 "Intel 82801I HD Audio" rev 0x03: msi
azalia0: codecs: Conexant CX20561
audio0 at azalia0
ppb0 at pci0 dev 28 function 0 "Intel 82801I PCIE" rev 0x03: msi
pci1 at ppb0 bus 2
ppb1 at pci0 dev 28 function 1 "Intel 82801I PCIE" rev 0x03: msi
pci2 at ppb1 bus 3
iwn0 at pci2 dev 0 function 0 "Intel WiFi Link 5300" rev 0x00: msi, MIMO 3T3R,
MoW, address 00:21:6a:8c:3d:9c
ppb2 at pci0 dev 28 function 3 "Intel 82801I PCIE" rev 0x03: msi
pci3 at ppb2 bus 5
uhci3 at pci0 dev 29 function 0 "Intel 82801I USB" rev 0x03: apic 1 int 16
uhci4 at pci0 dev 29 function 1 "Intel 82801I USB" rev 0x03: apic 1 int 17
uhci5 at pci0 dev 29 function 2 "Intel 82801I USB" rev 0x03: apic 1 int 18
ehci1 at pci0 dev 29 function 7 "Intel 82801I USB" rev 0x03: apic 1 int 19
usb1 at ehci1: USB revision 2.0
uhub1 at usb1 "Intel EHCI root hub" rev 2.00/1.00 addr 1
ppb3 at pci0 dev 30 function 0 "Intel 82801BAM Hub-to-PCI" rev 0x93
pci4 at ppb3 bus 13
pcib0 at pci0 dev 31 function 0 "Intel 82801IEM LPC" rev 0x03
ahci0 at pci0 dev 31 function 2 "Intel 82801I AHCI" rev 0x03: msi, AHCI 1.2
scsibus1 at ahci0: 32 targets
sd0 at scsibus1 targ 0 lun 0: <ATA, MKNSSDCR120GB, 507A> SCSI3 0/direct fixed
naa.0000120000000000
sd0: 114473MB, 512 bytes/sector, 234441648 sectors, thin
ichiic0 at pci0 dev 31 function 3 "Intel 82801I SMBus" rev 0x03: apic 1 int 23
iic0 at ichiic0
usb2 at uhci0: USB revision 1.0
uhub2 at usb2 "Intel UHCI root hub" rev 1.00/1.00 addr 1
usb3 at uhci1: USB revision 1.0
uhub3 at usb3 "Intel UHCI root hub" rev 1.00/1.00 addr 1
usb4 at uhci2: USB revision 1.0
uhub4 at usb4 "Intel UHCI root hub" rev 1.00/1.00 addr 1
usb5 at uhci3: USB revision 1.0
uhub5 at usb5 "Intel UHCI root hub" rev 1.00/1.00 addr 1
usb6 at uhci4: USB revision 1.0
uhub6 at usb6 "Intel UHCI root hub" rev 1.00/1.00 addr 1
usb7 at uhci5: USB revision 1.0
uhub7 at usb7 "Intel UHCI root hub" rev 1.00/1.00 addr 1
isa0 at pcib0
isadma0 at isa0
pckbc0 at isa0 port 0x60/5
pckbd0 at pckbc0 (kbd slot)
pckbc0: using irq 1 for kbd slot
wskbd0 at pckbd0: console keyboard, using wsdisplay0
pms0 at pckbc0 (aux slot)
pckbc0: using irq 12 for aux slot
wsmouse0 at pms0 mux 0
pcppi0 at isa0 port 0x61
spkr0 at pcppi0
aps0 at isa0 port 0x1600/31
uvideo0 at uhub0 port 6 configuration 1 interface 0 "Lenovo product 0x480c" rev
2.00/31.34 addr 2
video0 at uvideo0
vscsi0 at root
scsibus2 at vscsi0: 256 targets
softraid0 at root
scsibus3 at softraid0: 256 targets
root on sd0a (3b8dd424dbb39f54.a) swap on sd0b dump on sd0b
