Has the 11.2 RC2 kernel stolen a CPU?

hcvv · October 29, 2009, 8:31pm

On openSUSE 10.3 using cat /proc/cpuinfo I get::

processor       : 0
vendor_id       : GenuineIntel
cpu family      : 6
model           : 15
model name      : Genuine Intel(R) CPU            2140  @ 1.60GHz
stepping        : 2
cpu MHz         : 1600.000
cache size      : 1024 KB
physical id     : 0
siblings        : 2
core id         : 0
cpu cores       : 2
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 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc pni monitor ds_cpl est tm2 ssse3 cx16 xtpr lahf_lm
bogomips        : 3203.51
clflush size    : 64

processor       : 1
vendor_id       : GenuineIntel
cpu family      : 6
model           : 15
model name      : Genuine Intel(R) CPU            2140  @ 1.60GHz
stepping        : 2
cpu MHz         : 1600.000
cache size      : 1024 KB
physical id     : 0
siblings        : 2
core id         : 1
cpu cores       : 2
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 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc pni monitor ds_cpl est tm2 ssse3 cx16 xtpr lahf_lm
bogomips        : 3200.93
clflush size    : 64

and on 11.2 RC2:

processor       : 0
vendor_id       : GenuineIntel
cpu family      : 6
model           : 15
model name      : Genuine Intel(R) CPU            2140  @ 1.60GHz
stepping        : 2
cpu MHz         : 1200.000
cache size      : 1024 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 est tm2 ssse3 cx16 xtpr pdcm lahf_lm
bogomips        : 3200.95
clflush size    : 64
power management:

And this is of course mirrored in places like My Computer.

Is the 11.2 kernel not seeing (and worse: not using) my hyperthreading or is there some other explanation?

knurpht · October 30, 2009, 10:00am

Henk, mine shows everything normal, on both systems. If it’s all over the place, could it be a degrading condition of the CPU?

Akoellh · October 30, 2009, 10:04am

Fact is:

All openSUSE kernels since 10.2 have SMP activated by default, the last version still having an extra “kernel-smp” was 10.1.

hcvv · October 30, 2009, 10:28am

@Knurpht
I do not think something being wrong in the hardware. I am now constanly rebooting between 10.3 and 11.2 and both are very consistent in what they say: **two **on 10.3 and **one **on 11.2.

@Akoellh
Kernel in my 10.3: 2.6.22.19-0.4-default.
Kernel in my 11.2 RC2: 2.6.31.5-0.1-desktop.
All rather normal I think. I originaly installed 11.2 RC1 from DVD and went to RC2 with zypper dup. This would give me the correct kernel would it?

Akoellh · October 30, 2009, 1:30pm

zgrep SMP /proc/config.gz

hcvv · October 30, 2009, 1:59pm

Same system running 10.3:

CONFIG_SMP=y
# CONFIG_X86_BIGSMP is not set
CONFIG_SUSPEND_SMP=y
CONFIG_X86_FIND_SMP_CONFIG=y
CONFIG_X86_SMP=y

and 11.2

CONFIG_USE_GENERIC_SMP_HELPERS=y
CONFIG_X86_32_SMP=y
CONFIG_SMP=y
CONFIG_X86_BIGSMP=y
CONFIG_PM_SLEEP_SMP=y
CONFIG_SCSI_SAS_HOST_SMP=y
CONFIG_VIDEO_VP27SMPX=m

Thanks for looking into this.

Akoellh · October 30, 2009, 3:14pm

Just installed “kernel-desktop” on my 11.2 test installation (i586, x86_64 is still updating to rc2) and it shows me both CPUs.

Although “only” a VM, the cpus are “passed through”, so my result is accurate and as expected.

The kernel itself is certainly not the problem.

P.S.

A simple “uname -a” will also confirm SMP support.

lwfinger · October 30, 2009, 4:15pm

Please post the output of ‘dmesg | grep CPU’.

hcvv · October 30, 2009, 4:59pm

All below when running under 11.2.

uname -a:

Linux boven 2.6.31.5-0.1-desktop #1 SMP PREEMPT 2009-10-26 15:49:03 +0100 i686 i686 i386 GNU/Linux

dsmesg | grep CPU:

    0.000000]   Transmeta TransmetaCPU
    0.000000] Processor #0 (Bootup-CPU)
    0.000000] SMP: Allowing 2 CPUs, 0 hotplug CPUs
    0.000000] NR_CPUS:128 nr_cpumask_bits:128 nr_cpu_ids:2 nr_node_ids:8
    0.000000] PERCPU: Embedded 14 pages at c1a25000, static data 34204 bytes
    0.000000] Initializing CPU#0
    0.032061] CPU: L1 I cache: 32K, L1 D cache: 32K
    0.032065] CPU: L2 cache: 1024K
    0.032069] CPU: Physical Processor ID: 0
    0.032071] CPU: Processor Core ID: 0
    0.032076] mce: CPU supports 6 MCE banks
    0.032087] CPU0: Thermal monitoring enabled (TM2)
    0.052039] Brought up 1 CPUs
    0.052089] CPU0 attaching NULL sched-domain.
    0.500998] Switched to high resolution mode on CPU 0
    1.455278] processor LNXCPU:00: registered as cooling_device0
   19.243956] powernow: This module only works with AMD K7 CPUs
   55.014525] CPU0 attaching NULL sched-domain.
   55.014601] CPU0 attaching NULL sched-domain.

hcvv · October 30, 2009, 5:12pm

And below when under10.3

uname -a

Linux boven 2.6.22.19-0.4-default #1 SMP 2009-08-14 02:09:16 +0200 i686 i686 i386 GNU/Linux

dmesg | grep CPU

Initializing CPU#0
CPU: After generic identify, caps: bfebfbff 20100000 00000000 00000000 0000e39d 00000000 00000001
CPU: L1 I cache: 32K, L1 D cache: 32K
CPU: L2 cache: 1024K
CPU: Physical Processor ID: 0
CPU: Processor Core ID: 0
CPU: After all inits, caps: bfebfbff 20100000 00000000 00003940 0000e39d 00000000 00000001
Intel machine check reporting enabled on CPU#0.
CPU0: Intel Genuine Intel(R) CPU            2140  @ 1.60GHz stepping 02
Initializing CPU#1
CPU: After generic identify, caps: bfebfbff 20100000 00000000 00000000 0000e39d 00000000 00000001
CPU: L1 I cache: 32K, L1 D cache: 32K
CPU: L2 cache: 1024K
CPU: Physical Processor ID: 0
CPU: Processor Core ID: 1
CPU: After all inits, caps: bfebfbff 20100000 00000000 00003940 0000e39d 00000000 00000001
Intel machine check reporting enabled on CPU#1.
CPU1: Intel Genuine Intel(R) CPU            2140  @ 1.60GHz stepping 02
checking TSC synchronization [CPU#0 -> CPU#1]: passed.
Brought up 2 CPUs
Switched to NOHz mode on CPU #0
Switched to NOHz mode on CPU #1
powernow: This module only works with AMD K7 CPUs

user · October 30, 2009, 5:25pm

hcvv wrote:

> Code:
> --------------------
> 0.000000] Transmeta TransmetaCPU

Uh?

Yours is no a Transmeta CPU, it’s an Intel Dual Core :-?

Greetings,

–
Camaleón

hcvv · October 30, 2009, 5:30pm

The system is an HP{ Pavilion Slimline s3160.nl.
They say it has a Pentium E2140 (C) 1,6 GHz CPU.

And that is what the 10.3 kernel says likewise.
How can such a thing happen???
(I haven’t even heard of such a thing as Transmeta)

Akoellh · October 30, 2009, 6:02pm

Very odd behavior indeed, but just to be sure, that there is no bad boot parameter, show us the output.

cat /proc/cmdline

Cough, as a “Disciple of Linus the Great”, you should have (hint, read the WP article about Linus).

user · October 30, 2009, 5:56pm

hcvv wrote:

> The system is an HP{ Pavilion Slimline s3160.nl.
> They say it has a Pentium E2140 (C) 1,6 GHz CPU.
>
> And that is what the 10.3 kernel says likewise.
> How can such a thing happen???
> (I haven’t even heard of such a thing as Transmeta)

Look this thread:

A core missing!
http://ubuntuforums.org/showthread.php?t=1142333

And:

After upgrade to version 9.04, Ubuntu uses only one processor.
https://bugs.launchpad.net/ubuntu/+bug/371210

It seems you are facing some similar problem :-?

Greetings,

–
Camaleón

oldcpu · October 30, 2009, 6:40pm

It does not seem to be a global problem. For example my Intel core i7 920 shows all cores with “dmesg | grep CPU” when booting to the openSUSE-11.2 RC2 64-bit KDE-4.3.1 liveCD : pastebin - dmesg output - post number 1649487

hcvv · October 30, 2009, 6:51pm

On 11.2 cat /proc/cmdline:

root=/dev/disk/by-id/ata-Hitachi_HDT725032VLA380_VFJ201R23XUEXW-part5 nolapic resume=/dev/disk/by-id/ata-Hitachi_HDT725032VLA380_VFJ201R23XUEXW-part1 splash=silent quiet vga=0x31a

An yes, after Camaleón mentioned Transmeta I did some Wikipedia reading.

I am not quite sure I understand all the stuff in Camaleón’s links, but I tried to boot with acpi=off and with noapic (not with both at the same time. Didn’t help. Maybe I just tried the wrong thing.

I remember that when booting the 11.2 RC2 DVD it ended up in a loop after loading the kernel. I then tried playing with the F-keys and the parameters until it did. I am not quite sure which one (also some acpi), but will try later to reconstruct this (first the wife calls for dinner ).

Strange imho is also that also it says Transmeta in the first place, it says Intel on the My Computer page.

And to make the story complete, here is /proic/cmdline from 10.3:

root=/dev/disk/by-id/scsi-SATA_Hitachi_HDT7250_VFJ201R23XUEXW-part2 vga=0x31a resume=/dev/sda1 splash=silent

And that brings me the main extra one there: nolapic. Shall I try without it?

Akoellh · October 30, 2009, 6:53pm

Japp, remove the “nolapic” for a start.

hcvv · October 30, 2009, 7:53pm

Removing the “nolapic” resulted in a loop while booting. Black screen for a while and then a system start.

user · October 30, 2009, 8:41pm

hcvv wrote:

> Removing the “nolapic” resulted in a loop while booting. Black screen
> for a while and then a system start.

O.k, then try first booting with the “safe-setting” option of the Grub menu
(which I guess auto-disables acpi, apic and so) and then check again if the
2 cores are present.

Greetings,

–
Camaleón

hcvv · October 30, 2009, 8:56pm

Sorry I did not tell this, but direct after the boot loop I tried “Safe Settings”. It booted, but only one CPU.