acpi off and only one core

[hpg]

Since I am on maverick, I experience very bad video and audio playback. Sound and picture hangs, jumps back and forth.
I tried to turn off acpi and added kernel parameter acpi=off.
After rebooting, video playback was fine, everything smooth. But then I discovered in system monitor, that only one cpu was present. cpuinfo-freq gives this result:

cpufrequtils 007: cpufreq-info (C) Dominik Brodowski 2004-2009
Report errors and bugs to cpufreq@vger.kernel.org, please.
analyzing CPU 0:
no or unknown cpufreq driver is active on this CPU
maximum transition latency: 0.00 ms.

I removed the acpi kernel option and after rebooting the system, I saw 3 cores and videoplayback was a pain again.

Any ideas what goes wrong here?

[molostoff]

Re: acpi off and only one core

Try 'lscpu' and post it's output here to review.....

[hpg]

Re: acpi off and only one core

Hi

This is the output of lscpu:

root@hp:~# lscpu
Architecture: i686
CPU op-mode(s): 64-bit
CPU(s): 1
Thread(s) per core: 1
Core(s) per socket: 1
CPU socket(s): 1
Vendor ID: AuthenticAMD
CPU family: 16
Model: 2
Stepping: 3
CPU MHz: 2294.037
Virtualisation: AMD-V
L1d cache: 64K
L1i cache: 64K
L2 cache: 512K
L3 cache: 2048K


I have also attached a syslog file. This contains the logs of two boots.
The first boot is from Oct,29. with ACPI enabled. The second boot is from Nov,6. with ACPI disabled.
It does not hold any useful information for me, but maybe a more experienced person may see some
hints on what is going on here.

[abalone]

Re: acpi off and only one core

I'm not a more experienced person, but I do remember getting only one core (out of two) up and running when booting without the kernel parameter noapic. Dunno if that has anything at all to do with ...anything.

[molostoff]

Re: acpi off and only one core

I'm not a more experienced person, but I do remember getting only one core (out of two) up and running when booting without the kernel parameter noapic. Dunno if that has anything at all to do with ...anything.

syslog.txt empty

As there in 10.10 was kernel update, you can check booting with previous (from 10.04) kernels to see the result. It seems that a kernel patch from amd can solve it.
Also I can suggest to establish correct model/stepping of your amd via http://en.wikipedia.org/wiki/AMD_K10
and ensure that your bios is up to date.

acpi=off refers to ignore bios configuration settings. Please, observe http://www.mjmwired.net/kernel/Docum...parameters.txt

[hpg]

Re: acpi off and only one core

Ok, here are two versions of the syslog. One with, the other without acpi.

[molostoff]

Re: acpi off and only one core

Ok, here are two versions of the syslog. One with, the other without acpi.

Have you installed i386 version of kubuntu (or x64 one)?

Im not so closest to AMD cpus, but it seems to me that there are indeed 3 cores:
http://www.cpu-world.com/CPUs/K10/AMD-Phenom%20X3%208600B%20-%20HD860BWCJ3BGH%20(HD860BWCGHBOX).html
(dig yself if im wrong here)

acpi=off disables use of bios-stored (manufacturer prepared) configuration data for your machine and instructs kernel to determine hw configuration by self/defaults.

So the verdict is if you dont want to see acpi=off on kernel command line simply upgrade your bios to the latest version.

Also you should try to disable (remove) clocksource=acpi_pm parameter or use clocksource=hpet instead.

videoplayback is stable (and acceptable) on radeon drivers, you might want to use them instead of fglrx

[hpg]

Re: acpi off and only one core

I guess I found out who is responsible for all this strange behaviour: It's the fglrx proprietary driver.
This is what I was tried with the 2.6.35-23-generic kernel:

fglrx and noacpi brings smooth video and audio playback
fglrx and acpi makes playback jump and hang. Maybe fglrx is responsible for my ridiculous slow system clock.
radeon driver and acpi, everything is smooth and fine.

I'll go and tell the fglrx guys. Lets see what they think about this.

Many thanks for the help!