12 Sep
2008
12 Sep
'08
11:20 a.m.
I am running Ubuntu studio 64 on a Thinkpad laptop (X61s), and
i get an horrible battery life. Powertop suggest to configure the
kernel with CONFIG_NO_HZ=y.
How does this interact with the -rt kernel (2.6.24) used in Ubuntu Studio ? Any good
reason to don't do it ?
And in case, where i find the ubuntu studio kernel source ?
Thanks and sorry for the FAQ like questions,
Maurizio De Cecco
14 Sep
14 Sep
10:38 a.m.
Hi Maurizio
2008/9/12 Maurizio De Cecco <jmax(a)dececco.name>me>:
I am running Ubuntu studio 64 on a Thinkpad laptop
(X61s), and
i get an horrible battery life.
I don't know the Ubuntu Kernel, but they might have disabled acpi,
cpu-freq-scaling, at either boot time or in the kernel.
Powertop suggest to configure the
kernel with CONFIG_NO_HZ=y.
I have CONFIG_NO_HZ=n
and CONFIG_HZ=1000
- works well here. (linux 2.6.25)
And in case, where i find the ubuntu studio kernel source ?
In the ubuntu source repository ?
May be enabled in /etc/apt/sources.list
Sincerely
Emanuel
15 Sep
15 Sep
3 p.m.
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Maurizio De Cecco wrote:
I am running Ubuntu studio 64 on a Thinkpad laptop
(X61s), and i get
an horrible battery life. Powertop suggest to configure the kernel
with CONFIG_NO_HZ=y.
How does this interact with the -rt kernel (2.6.24) used in Ubuntu
Studio ? Any good reason to don't do it ?
I can't think of any. On the contrary with NO_HZ an X60s can get down to
under 10W. I'm using tickless realtime kernels ever since the NO_HZ
option was available. At 2.6.19 I measured MIDI latency/jitter around
1kHz/1ms using NO_HZ on i686.
Audio I/O works just fine on tickless 2.6.24-rt - there are no X-Runs
with JACK under normal operation even down to 256fpp on USB.
And in case, where i find the ubuntu studio kernel
source ?
I have no idea ;) you can try `apt-cache search kernel | grep 2.6.24`
and `apt-get install linux-source-2.6.24...`
Instead of compiling your own, you can also try to use the kernel from
64studio (it's also debian based) which IIRC is tickless:
http://apt.64studio.com/64studio/stable/pool/main/l/linux-2.6/
install with `sudo dpkg -i linux-image...deb` - You can find more
information on compiling and post-compilation setup notes here:
http://64studio.com/node/504
Maybe you also find the config and patches from pure-dyne useful. They
use ubuntustudio-kernel patches and provide diffs that works with a
vanilla kernel from kernel.org - see
https://code.goto10.org/projects/puredyne/browser/live/kernel/2.6.24
HTH,
robin
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16 Sep
16 Sep
7:36 a.m.
Hi Robin
Instead of compiling your own, you can also try to use
the kernel from
64studio (it's also debian based) which IIRC is tickless:
http://apt.64studio.com/64studio/stable/pool/main/l/linux-2.6/
I'm afraid that particular kernel is not tickless, it was never intended
for power-saving:
$ grep NO_HZ /boot/config-2.6.21-1-multimedia-amd64
# CONFIG_NO_HZ is not set
We are looking at the tickless feature for power savings on the Indamixx
though.
Cheers!
Daniel
17 Sep
17 Sep
8:36 p.m.
Hi,
sorry for newbe question...
"Tickless" option while configuring new kernel is good only for power saving?
No other benefits?
Thanks
mira
< ------------ Původní zpráva ------------
< Od: Daniel James <daniel(a)64studio.com>
< Předmět: Re: [LAT] Tickless kernel and realtime
< Datum: 16.9.2008 11:36:14
< ----------------------------------------
< Hi Robin
<
< > Instead of compiling your own, you can also try to use the kernel from
< > 64studio (it's also debian based) which IIRC is tickless:
< > http://apt.64studio.com/64studio/stable/pool/main/l/linux-2.6/
<
< I'm afraid that particular kernel is not tickless, it was never intended
< for power-saving:
<
< $ grep NO_HZ /boot/config-2.6.21-1-multimedia-amd64
< # CONFIG_NO_HZ is not set
<
< We are looking at the tickless feature for power savings on the Indamixx
< though.
<
< Cheers!
<
< Daniel
<
<
< _______________________________________________
< Linux-audio-tuning mailing list
< Linux-audio-tuning(a)lists.linuxaudio.org
< http://lists.linuxaudio.org/listinfo/linux-audio-tuning
<
<
<
18 Sep
18 Sep
12:47 p.m.
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Jaromír Mikeš wrote:
Hi,
sorry for newbe question...
"Tickless" option while configuring new kernel is good only for power saving?
No other benefits?
It changes the way timer interrupts are triggered. tickless means only
on demand.
There may be scheduling benefits, but they can probably be neglected:
timer-interrupts are handled quickly, NTL cause the CPU to //wake-up and
consume more power//.
robin
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5:42 p.m.
It changes the way timer interrupts are triggered.
tickless means only
on demand.
There may be scheduling benefits, but they can probably be neglected:
timer-interrupts are handled quickly, NTL cause the CPU to //wake-up and
consume more power//.
It is possible to say it is generally good for RT kernel?
Thanks for help
Mira
5699
days inactive
5705
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linux-audio-tuning@lists.linuxaudio.org
6 comments
5 participants
participants (5)
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Daniel James -
Emanuel Rumpf -
Jaromír Mikeš -
Maurizio De Cecco -
Robin Gareus