After upgrade to version 9.04, Ubuntu uses only one processor.

[Jaakko Manninen]

I have run Ubuntu 8.10 on my Packard Bell EasyNote MH-35 laptop without problems. After upgrading to Ubuntu version 9.04, lap-top is slow and uses only one core. The processor is Intel Core Duo T8100. I have to use noapic nolapic boot options to get Ubuntu booting (also in the 8.10 version). I have tried to disable the USB mouse and keyboard support in BIOS (this was suggested as a solution on another lap-top) but in this case the system refuses to boot.
Below some more info.

# cat /proc/cpuinfo
processor : 0
vendor_id : GenuineIntel
cpu family : 6
model : 23
model name : Intel(R) Core(TM)2 Duo CPU T8100 @ 2.10GHz
stepping : 6
cpu MHz : 1200.000
cache size : 3072 KB
physical id : 0
siblings : 1
core id : 0
cpu cores : 1
apicid : 0
initial apicid : 0
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc arch_perfmon pebs bts pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm sse4_1 lahf_lm ida tpr_shadow vnmi flexpriority
bogomips : 4200.11
clflush size : 64
power management:

# dmesg | grep -i cpu
[ 0.000000] Initializing cgroup subsys cpuset
[ 0.000000] Initializing cgroup subsys cpu
[ 0.000000] KERNEL supported cpus:
[ 0.000000] Transmeta TransmetaCPU
[ 0.000000] ACPI: SSDT B7D9924D, 025F (r1 PmRef Cpu0Tst 3000 INTL 20050228)
[ 0.000000] ACPI: SSDT B7D991A7, 00A6 (r1 PmRef Cpu7Tst 3000 INTL 20050228)
[ 0.000000] ACPI: SSDT B7D99101, 00A6 (r1 PmRef Cpu6Tst 3000 INTL 20050228)
[ 0.000000] ACPI: SSDT B7D9905B, 00A6 (r1 PmRef Cpu5Tst 3000 INTL 20050228)
[ 0.000000] ACPI: SSDT B7D98FB5, 00A6 (r1 PmRef Cpu4Tst 3000 INTL 20050228)
[ 0.000000] ACPI: SSDT B7D98F0F, 00A6 (r1 PmRef Cpu3Tst 3000 INTL 20050228)
[ 0.000000] ACPI: SSDT B7D98E69, 00A6 (r1 PmRef Cpu2Tst 3000 INTL 20050228)
[ 0.000000] ACPI: SSDT B7D98DC3, 00A6 (r1 PmRef Cpu1Tst 3000 INTL 20050228)
[ 0.000000] ACPI: SSDT B7D979A9, 141A (r1 PmRef CpuPm 3000 INTL 20050228)
[ 0.000000] Processor #0 (Bootup-CPU)
[ 0.000000] SMP: Allowing 2 CPUs, 0 hotplug CPUs
[ 0.000000] PERCPU: Allocating 45056 bytes of per cpu data
[ 0.000000] NR_CPUS: 64, nr_cpu_ids: 2, nr_node_ids 1
[ 0.000000] Initializing CPU#0
[ 0.004000] SLUB: Genslabs=12, HWalign=64, Order=0-3, MinObjects=0, CPUs=2, Nodes=1
[ 0.004000] HPET: 3 timers in total, 0 timers will be used for per-cpu timer
[ 0.004000] Initializing cgroup subsys cpuacct
[ 0.004000] CPU: L1 I cache: 32K, L1 D cache: 32K
[ 0.004000] CPU: L2 cache: 3072K
[ 0.004000] CPU: Physical Processor ID: 0
[ 0.004000] CPU: Processor Core ID: 0
[ 0.532470] Brought up 1 CPUs
[ 0.532488] CPU0 attaching NULL sched-domain.
[ 0.568016] Switched to high resolution mode on CPU 0
[ 1.643118] cpufreq: No nForce2 chipset.
[ 1.664851] ACPI: SSDT B7D99D67, 0261 (r1 PmRef Cpu0Ist 3000 INTL 20050228)
[ 1.668409] ACPI: SSDT B7D994AC, 0518 (r1 PmRef Cpu0Cst 3001 INTL 20050228)
[ 1.671438] ACPI: CPU0 (power states: C1[C1] C2[C2] C3[C3])
[ 1.671480] processor ACPI_CPU:00: registered as cooling_device1
[ 1.671488] ACPI: Processor [CPU0] (supports 8 throttling states)
[ 2.796475] cpuidle: using governor ladder
[ 2.796566] cpuidle: using governor menu
[ 43.694069] CPU0 attaching NULL sched-domain.
[ 43.694140] CPU0 attaching NULL sched-domain.

[Daniel Letzeisen (dtl131)]

I've marked it as confirmed based on multiple Intel C2D owners reporting similar output (kernel configured for Transmeta CPU's) in this ubuntuforums thread. http://ubuntuforums.org/showthread.php?t=1142333

[Daniel Letzeisen (dtl131)]

Nevermind, the kernel is configured correctly (I was thrown off by the grep cpu). It seems to be an ACPI issue.

[Jaakko Manninen (mannisenjaakko)]

OK,
and thanks for your help. Indeed I seem to have some acpi problem, I get the message:
bios bug detected acpi #0 not found
at startup. I have updated the bios when I bought the laptop (in order to get Win XP running correctly) but the
problem persists. The bios update itself seemed to be buggy too since the network adapter disappears in
XP after the bios update and one needs to run another update in order to get the network card functioning again. None of this seemed to affect Ubuntu, though, and all the peripherals function in Linux as they should.

[malev (marcosvanetta)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. You reported this bug a while ago and there hasn't been any activity in it recently. We were wondering if this is still an issue for you. Can you try with the latest Ubuntu release? Thanks in advance.

[Jaakko Manninen (mannisenjaakko)]

I found a solution to this problem. Before, I needed to boot with options
noapic nolapic
which caused the machine to bring up one core only. Replacing the boot
options
as follows
noapic nolapic --> pci=assign-busses apicmaintimer idle=poll
reboot=cold,hard
fixed the problem on my machine. Since I got both cores running quite
recently
only, I think I will stay with the working configuration for a while before
upgrading to
the Ubuntu version 9.10

On Fri, Dec 18, 2009 at 1:48 AM, malev <email address hidden> wrote:

> Thank you for taking the time to report this bug and helping to make
> Ubuntu better. You reported this bug a while ago and there hasn't been
> any activity in it recently. We were wondering if this is still an issue
> for you. Can you try with the latest Ubuntu release? Thanks in advance.
>
> ** Changed in: ubuntu
> Status: Confirmed => Incomplete
>
> --
> After upgrade to version 9.04, Ubuntu uses only one processor.
> https://bugs.launchpad.net/bugs/371210
> You received this bug notification because you are a direct subscriber
> of the bug.
>
> Status in Ubuntu: Incomplete
>
> Bug description:
> I have run Ubuntu 8.10 on my Packard Bell EasyNote MH-35 laptop without
> problems. After upgrading to Ubuntu version 9.04, lap-top is slow and uses
> only one core. The processor is Intel Core Duo T8100. I have to use noapic
> nolapic boot options to get Ubuntu booting (also in the 8.10 version). I
> have tried to disable the USB mouse and keyboard support in BIOS (this was
> suggested as a solution on another lap-top) but in this case the system
> refuses to boot.
> Below some more info.
>
> # cat /proc/cpuinfo
> processor : 0
> vendor_id : GenuineIntel
> cpu family : 6
> model : 23
> model name : Intel(R) Core(TM)2 Duo CPU T8100 @ 2.10GHz
> stepping : 6
> cpu MHz : 1200.000
> cache size : 3072 KB
> physical id : 0
> siblings : 1
> core id : 0
> cpu cores : 1
> apicid : 0
> initial apicid : 0
> fdiv_bug : no
> hlt_bug : no
> f00f_bug : no
> coma_bug : no
> fpu : yes
> fpu_exception : yes
> cpuid level : 10
> wp : yes
> flags : fpu vme de pse tsc msr pae mce cx8 sep mtrr pge mca cmov
> pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc
> arch_perfmon pebs bts pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr
> pdcm sse4_1 lahf_lm ida tpr_shadow vnmi flexpriority
> bogomips : 4200.11
> clflush size : 64
> power management:
>
> # dmesg | grep -i cpu
> [ 0.000000] Initializing cgroup subsys cpuset
> [ 0.000000] Initializing cgroup subsys cpu
> [ 0.000000] KERNEL supported cpus:
> [ 0.000000] Transmeta TransmetaCPU
> [ 0.000000] ACPI: SSDT B7D9924D, 025F (r1 PmRef Cpu0Tst 3000 INTL
> 20050228)
> [ 0.000000] ACPI: SSDT B7D991A7, 00A6 (r1 PmRef Cpu7Tst 3000 INTL
> 20050228)
> [ 0.000000] ACPI: SSDT B7D99101, 00A6 (r1 PmRef Cpu6Tst 3000 INTL
> 20050228)
> [ 0.000000] ACPI: SSDT B7D9905B, 00A6 (r1 PmRef Cpu5Tst 3000 INTL
> 20050228)
> [ 0.000000] ACPI: SSDT B7D98FB5, 00A6 (r1 PmRe...