After some last updates I only have 4 cores (have 8 cores)

I've updated my system.

Mate-system-monitor now shows me only 4 CPU cores although I have 8 CPU cores.

What could be the reason?

Last week I had all 8 CPU cores under mate-system-monitor.

Please help, thanks!

I suspect something probably disabled hyperthreading - could be a kernel mitigation for one of those CPU vulnerabilities that keep popping up these days...

Hello,

It would help if you gave us the output of inxi -Fxxz

Kernel: 5.0.0-36-generic
Distro: Ubuntu 19.04 (Disco Dingo)
CPU: Quad Core model: AMD FX-8350 bits: 64 type: MCP arch: Bulldozer L1

Very strange, I have an 8 core processor.

I remember four days ago, amd64-microcode was updated.

lshw -C cpu

*-cpu                     
       description: CPU
       product: AMD FX(tm)-8350 Eight-Core Processor
       vendor: Advanced Micro Devices [AMD]
       physical id: 4
       bus info: cpu@0
       version: AMD FX(tm)-8350 Eight-Core Processor
       serial: To Be Filled By O.E.M.
       slot: Socket 942
       size: 4GHz
       capacity: 4GHz
       width: 64 bits
       clock: 200MHz
       capabilities: x86-64 fpu fpu_exception wp vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp constant_tsc rep_good nopl nonstop_tsc cpuid extd_apicid aperfmperf pni pclmulqdq monitor ssse3 fma cx16 sse4_1 sse4_2 popcnt aes xsave avx f16c lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs xop skinit wdt fma4 tce nodeid_msr tbm topoext perfctr_core perfctr_nb cpb hw_pstate pti ssbd ibpb vmmcall bmi1 arat npt lbrv svm_lock nrip_save tsc_scale vmcb_clean flushbyasid decodeassists pausefilter pfthreshold
       configuration: cores=8 enabledcores=8 threads=8
  *-processor UNCLAIMED

cat /proc/cpuinfo

processor	: 0
vendor_id	: AuthenticAMD
cpu family	: 21
model		: 2
model name	: AMD FX(tm)-8350 Eight-Core Processor
stepping	: 0
microcode	: 0x6000852
cpu MHz		: 4012.986
cache size	: 2048 KB
physical id	: 0
siblings	: 4
core id		: 0
cpu cores	: 4
apicid		: 16
initial apicid	: 0
fpu		: yes
fpu_exception	: yes
cpuid level	: 13
wp		: yes
flags		: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm constant_tsc rep_good nopl nonstop_tsc cpuid extd_apicid aperfmperf pni pclmulqdq monitor ssse3 fma cx16 sse4_1 sse4_2 popcnt aes xsave avx f16c lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs xop skinit wdt fma4 tce nodeid_msr tbm topoext perfctr_core perfctr_nb cpb hw_pstate pti ssbd ibpb vmmcall bmi1 arat npt lbrv svm_lock nrip_save tsc_scale vmcb_clean flushbyasid decodeassists pausefilter pfthreshold
bugs		: fxsave_leak sysret_ss_attrs null_seg spectre_v1 spectre_v2 spec_store_bypass
bogomips	: 8027.08
TLB size	: 1536 4K pages
clflush size	: 64
cache_alignment	: 64
address sizes	: 48 bits physical, 48 bits virtual
power management: ts ttp tm 100mhzsteps hwpstate cpb eff_freq_ro

processor	: 2
vendor_id	: AuthenticAMD
cpu family	: 21
model		: 2
model name	: AMD FX(tm)-8350 Eight-Core Processor
stepping	: 0
microcode	: 0x6000852
cpu MHz		: 4012.933
cache size	: 2048 KB
physical id	: 0
siblings	: 4
core id		: 2
cpu cores	: 4
apicid		: 18
initial apicid	: 2
fpu		: yes
fpu_exception	: yes
cpuid level	: 13
wp		: yes
flags		: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm constant_tsc rep_good nopl nonstop_tsc cpuid extd_apicid aperfmperf pni pclmulqdq monitor ssse3 fma cx16 sse4_1 sse4_2 popcnt aes xsave avx f16c lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs xop skinit wdt fma4 tce nodeid_msr tbm topoext perfctr_core perfctr_nb cpb hw_pstate pti ssbd ibpb vmmcall bmi1 arat npt lbrv svm_lock nrip_save tsc_scale vmcb_clean flushbyasid decodeassists pausefilter pfthreshold
bugs		: fxsave_leak sysret_ss_attrs null_seg spectre_v1 spectre_v2 spec_store_bypass
bogomips	: 8027.08
TLB size	: 1536 4K pages
clflush size	: 64
cache_alignment	: 64
address sizes	: 48 bits physical, 48 bits virtual
power management: ts ttp tm 100mhzsteps hwpstate cpb eff_freq_ro

processor	: 4
vendor_id	: AuthenticAMD
cpu family	: 21
model		: 2
model name	: AMD FX(tm)-8350 Eight-Core Processor
stepping	: 0
microcode	: 0x6000852
cpu MHz		: 4012.535
cache size	: 2048 KB
physical id	: 0
siblings	: 4
core id		: 4
cpu cores	: 4
apicid		: 20
initial apicid	: 4
fpu		: yes
fpu_exception	: yes
cpuid level	: 13
wp		: yes
flags		: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm constant_tsc rep_good nopl nonstop_tsc cpuid extd_apicid aperfmperf pni pclmulqdq monitor ssse3 fma cx16 sse4_1 sse4_2 popcnt aes xsave avx f16c lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs xop skinit wdt fma4 tce nodeid_msr tbm topoext perfctr_core perfctr_nb cpb hw_pstate pti ssbd ibpb vmmcall bmi1 arat npt lbrv svm_lock nrip_save tsc_scale vmcb_clean flushbyasid decodeassists pausefilter pfthreshold
bugs		: fxsave_leak sysret_ss_attrs null_seg spectre_v1 spectre_v2 spec_store_bypass
bogomips	: 8027.08
TLB size	: 1536 4K pages
clflush size	: 64
cache_alignment	: 64
address sizes	: 48 bits physical, 48 bits virtual
power management: ts ttp tm 100mhzsteps hwpstate cpb eff_freq_ro

processor	: 6
vendor_id	: AuthenticAMD
cpu family	: 21
model		: 2
model name	: AMD FX(tm)-8350 Eight-Core Processor
stepping	: 0
microcode	: 0x6000852
cpu MHz		: 4013.095
cache size	: 2048 KB
physical id	: 0
siblings	: 4
core id		: 6
cpu cores	: 4
apicid		: 22
initial apicid	: 6
fpu		: yes
fpu_exception	: yes
cpuid level	: 13
wp		: yes
flags		: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm constant_tsc rep_good nopl nonstop_tsc cpuid extd_apicid aperfmperf pni pclmulqdq monitor ssse3 fma cx16 sse4_1 sse4_2 popcnt aes xsave avx f16c lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs xop skinit wdt fma4 tce nodeid_msr tbm topoext perfctr_core perfctr_nb cpb hw_pstate pti ssbd ibpb vmmcall bmi1 arat npt lbrv svm_lock nrip_save tsc_scale vmcb_clean flushbyasid decodeassists pausefilter pfthreshold
bugs		: fxsave_leak sysret_ss_attrs null_seg spectre_v1 spectre_v2 spec_store_bypass
bogomips	: 8027.08
TLB size	: 1536 4K pages
clflush size	: 64
cache_alignment	: 64
address sizes	: 48 bits physical, 48 bits virtual
power management: ts ttp tm 100mhzsteps hwpstate cpb eff_freq_ro

/usr/bin/software-properties-gtk

Can't see:
: Using Processor microcode firmware for AMD CPUs from amd64-microcode

amd64-microcode installed version: 3.20191021.1ubuntu0.19.04.1

dmesg | grep 'microcode'

[ 7.582867] microcode: microcode updated early to new patch_level=0x06000852
[ 7.582912] microcode: CPU0: patch_level=0x06000852
[ 7.582923] microcode: CPU2: patch_level=0x06000852
[ 7.582930] microcode: CPU4: patch_level=0x06000852
[ 7.582939] microcode: CPU6: patch_level=0x06000852
[ 7.583007] microcode: Microcode Update Driver: v2.2.

can it be a bug in last amd64-microcode package?

If all else fails, try a fresh install on a separate media, except install Synaptic and install system-critical packages one at a time.

@ tiox,

my system is working fine. Why should I make a fresh installation?

The CPU microcode error occurs after the current update of amd64-microcode.

I hope that the bug will be fixed soon because 4 days ago I had
still 8 CPU cores under "mate-system-monitor".

Well if that is the case, then you should be able to downgrade the kernel, hold the downgraded kernel (so autoremove doesn't touch it) and switch kernels when booting with GRUB in advanced options.

If you had not wiped your previous kernels yet, try an older kernel and see if that fixes it.

Ok, I'll try that out.

I can't report this problem to Ubuntu Mate Bug Tracker because I can't login anymore.

Oops!
Sorry, something just went wrong in Launchpad.

We’ve recorded what happened, and we’ll fix it as soon as possible. Apologies for the inconvenience.

(Error ID: OOPS-01f0dd804bde3680e42c4c25acef0b55)

Went back to kernel 5.0.0-35-generic and the problem on top this thread I posted is still present.

After updated the amd64-microcode package to version "3.20191021.1ubuntu0.19.04.1" I only
have 4 cores running but 4 days ago I have 8 cores running in Ubuntu-Mate 19.04.

It must be a bug in the amd64-microcode.

Is there a older version of the amd64-microcode available? I can't find an older version.

I removed the amd64-microcode.

lshw -C cpu

*-cpu
description: CPU
product: AMD FX(tm)-8350 Eight-Core Processor
vendor: Advanced Micro Devices [AMD]
physical id: 4
bus info: cpu@0
version: AMD FX(tm)-8350 Eight-Core Processor
serial: To Be Filled By O.E.M.
slot: Socket 942
size: 4GHz
capacity: 4GHz
width: 64 bits
clock: 200MHz
capabilities: x86-64 fpu fpu_exception wp vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp constant_tsc rep_good nopl nonstop_tsc cpuid extd_apicid aperfmperf pni pclmulqdq monitor ssse3 fma cx16 sse4_1 sse4_2 popcnt aes xsave avx f16c lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs xop skinit wdt fma4 tce nodeid_msr tbm topoext perfctr_core perfctr_nb cpb hw_pstate pti ssbd ibpb vmmcall bmi1 arat npt lbrv svm_lock nrip_save tsc_scale vmcb_clean flushbyasid decodeassists pausefilter pfthreshold
configuration: cores=8 enabledcores=8 threads=8
*-processor UNCLAIMED

configuration: cores=8 enabledcores=8 threads=8

Why "mate-system-monitor" shows me only 4 cores when "mate-system-monitor" shows me 4 days ago 8 cores.

Hello mate2go

Just a thought, how many cores do you see when you run htop? :face_with_head_bandage:

@ alpinejohn,

with htop only 4 cores. :frowning:

I booted with Ubuntu-Mate 18.10 Live-DVD.

"mate-system-monitor" ...it shows me there 8 cores... look at picture.

What the f*ck is that? :confused:

cat /proc/cpuinfo | grep "cpu cores" | uniq

Output:
cpu cores : 4

lscpu

Output:

Architecture: x86_64
CPU op-mode(s): 32-bit, 64-bit
Byte Order: Little Endian
Address sizes: 48 bits physical, 48 bits virtual
CPU(s): 8
On-line CPU(s) list: 0,2,4,6
Off-line CPU(s) list: 1,3,5,7
Thread(s) per core: 1
Core(s) per socket: 4
Socket(s): 1
NUMA node(s): 1
Vendor ID: AuthenticAMD
CPU family: 21
Model: 2
Model name: AMD FX(tm)-8350 Eight-Core Processor
Stepping: 0
CPU MHz: 4012.891
BogoMIPS: 8026.95
Virtualization: AMD-V
L1d cache: 16K
L1i cache: 64K
L2 cache: 2048K
L3 cache: 8192K
NUMA node0 CPU(s): 0,2,4,6
Flags: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm constant_tsc rep_good nopl nonstop_tsc cpuid extd_apicid aperfmperf pni pclmulqdq monitor ssse3 fma cx16 sse4_1 sse4_2 popcnt aes xsave avx f16c lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs xop skinit wdt fma4 tce nodeid_msr tbm topoext perfctr_core perfctr_nb cpb hw_pstate pti ssbd ibpb vmmcall bmi1 arat npt lbrv svm_lock nrip_save tsc_scale vmcb_clean flushbyasid decodeassists pausefilter pfthreshold

look here:
On-line CPU(s) list: 0,2,4,6
???
Off-line CPU(s) list: 1,3,5,7

are CPU core 1,3,5,7 offline? How to enable them?

I login with root account, I'll did:

echo 1 > /sys/devices/system/cpu/cpu0/online
echo 1 > /sys/devices/system/cpu/cpu1/online
echo 1 > /sys/devices/system/cpu/cpu2/online
echo 1 > /sys/devices/system/cpu/cpu3/online
echo 1 > /sys/devices/system/cpu/cpu4/online
echo 1 > /sys/devices/system/cpu/cpu5/online
echo 1 > /sys/devices/system/cpu/cpu6/online
echo 1 > /sys/devices/system/cpu/cpu7/online

Output:
bash: /sys/devices/system/cpu/cpu0/online: Permission denied
/bin/echo: write error: Operation not permitted

I run:

maxcpus=8

ls /sys/devices/system/cpu

Output:
cpu0 cpu2 cpu4 cpu6
cpu1 cpu3 cpu5 cpu7

"mate-system-monitor" shows still 4 cores :frowning:

core 1,3,5,7 are still offline...