[SOLVED] PVE 2.3: no multicore/hyperthreading

[Aleksandrs]

Hello,

I have a strange problem with PVE2.3 (2.6.32-18-pve):
On a machine with two Xeon(R) CPU E5-2620 processors cpuinfo only shows two cpus, although it should show 24 of them.

cpuinfo | grep ^processor | wc -l
2

All cores as well as hyperthreading support are enabled in BIOS.
Booting from a livecd (tried Debian 6.0.6, Centos 6.3, SystemRescueCD) produces correct results:

cpuinfo | grep ^processor | wc -l
24

 

[tom]

what do you get from:

cat /proc/cpuinfo

 

[Aleksandrs]

Here you go:

processor       : 0
vendor_id       : GenuineIntel
cpu family      : 6
model           : 45
model name      : Intel(R) Xeon(R) CPU E5-2620 0 @ 2.00GHz
stepping        : 7
cpu MHz         : 2000.188
cache size      : 15360 KB
physical id     : 0
siblings        : 1
core id         : 0
cpu cores       : 1
apicid          : 0
initial apicid  : 0
fpu             : yes
fpu_exception   : yes
cpuid level     : 13
wp              : yes
flags           : fpu vme de pse tsc msr pae mce cx8 apic mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts rep_good xtopology nonstop_tsc aperfmperf pni pclmulqdq dtes64 monitor ds_cpl vmx smx est tm2 ssse3 cx16 xtpr pdcm dca sse4_1 sse4_2 x2apic popcnt aes xsave avx lahf_lm ida arat epb xsaveopt pln pts dts tpr_shadow vnmi flexpriority ept vpid
bogomips        : 4000.37
clflush size    : 64
cache_alignment : 64
address sizes   : 46 bits physical, 48 bits virtual
power management:

processor       : 1
vendor_id       : GenuineIntel
cpu family      : 6
model           : 45
model name      : Intel(R) Xeon(R) CPU E5-2620 0 @ 2.00GHz
stepping        : 7
cpu MHz         : 2000.188
cache size      : 15360 KB
physical id     : 1
siblings        : 1
core id         : 0
cpu cores       : 1
apicid          : 32
initial apicid  : 32
fpu             : yes
fpu_exception   : yes
cpuid level     : 13
wp              : yes
flags           : fpu vme de pse tsc msr pae mce cx8 apic mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts rep_good xtopology nonstop_tsc aperfmperf pni pclmulqdq dtes64 monitor ds_cpl vmx smx est tm2 ssse3 cx16 xtpr pdcm dca sse4_1 sse4_2 x2apic popcnt aes xsave avx lahf_lm ida arat epb xsaveopt pln pts dts tpr_shadow vnmi flexpriority ept vpid
bogomips        : 3999.43
clflush size    : 64
cache_alignment : 64
address sizes   : 46 bits physical, 48 bits virtual
power management:

 

[Aleksandrs]

Here:

processor       : 0
vendor_id       : GenuineIntel
cpu family      : 6
model           : 45
model name      : Intel(R) Xeon(R) CPU E5-2620 0 @ 2.00GHz
stepping        : 7
cpu MHz         : 2000.188
cache size      : 15360 KB
physical id     : 0
siblings        : 1
core id         : 0
cpu cores       : 1
apicid          : 0
initial apicid  : 0
fpu             : yes
fpu_exception   : yes
cpuid level     : 13
wp              : yes
flags           : fpu vme de pse tsc msr pae mce cx8 apic mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts rep_good xtopology nonstop_tsc aperfmperf pni pclmulqdq dtes64 monitor ds_cpl vmx smx est tm2 ssse3 cx16 xtpr pdcm dca sse4_1 sse4_2 x2apic popcnt aes xsave avx lahf_lm ida arat epb xsaveopt pln pts dts tpr_shadow vnmi flexpriority ept vpid
bogomips        : 4000.37
clflush size    : 64
cache_alignment : 64
address sizes   : 46 bits physical, 48 bits virtual
power management:

processor       : 1
vendor_id       : GenuineIntel
cpu family      : 6
model           : 45
model name      : Intel(R) Xeon(R) CPU E5-2620 0 @ 2.00GHz
stepping        : 7
cpu MHz         : 2000.188
cache size      : 15360 KB
physical id     : 1
siblings        : 1
core id         : 0
cpu cores       : 1
apicid          : 32
initial apicid  : 32
fpu             : yes
fpu_exception   : yes
cpuid level     : 13
wp              : yes
flags           : fpu vme de pse tsc msr pae mce cx8 apic mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts rep_good xtopology nonstop_tsc aperfmperf pni pclmulqdq dtes64 monitor ds_cpl vmx smx est tm2 ssse3 cx16 xtpr pdcm dca sse4_1 sse4_2 x2apic popcnt aes xsave avx lahf_lm ida arat epb xsaveopt pln pts dts tpr_shadow vnmi flexpriority ept vpid
bogomips        : 3999.43
clflush size    : 64
cache_alignment : 64
address sizes   : 46 bits physical, 48 bits virtual
power management:

 

[tom]

strange. any bios update for the mainboard bios? and try the latest kernel from pvetest (2.6.32-19)

 

[nz_monkey]

I have seen similar. Resolved it two different ways:

1. Upgraded bios

2. Upgraded kernel

The bios came out after the kernel. So we didnt actually require the kernel update

 

[adamb]

Sounds like a bios update to me. I have no issues seeing all 16 cores of my E5-2680.

 

[Aleksandrs]

Well, the problem was not with the kernel or the BIOS.
It was caused by acpi=off kernel command line argument, which was set according to the fencing wiki article (http://pve.proxmox.com/wiki/Fencing#Configure_nodes_to_boot_immediately_and_always_after_power_cycle).
The article should be updated with a warning.

 

[tom]

why should "acpi=off" disables CPU cores?

 

[Aleksandrs]

why should "acpi=off" disables CPU cores?

Honestly, I have no idea.
I am not the only one though: http://unix.stackexchange.com/questions/56703/kernel-not-detecting-multicore-cpu

 

[Robstarusa]

I've seen this same behavior several years ago in ubuntu when I was troubleshooting something. Fixing it required re-enabling acpi....

 

[tom]

is there a bios upgrade for your mainboard?

 

[Aleksandrs]

is there a bios upgrade for your mainboard?

There was an UEFI update, but it did not fix the issue.