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While using the server, we have confirmed that the clock speed is very low only for a specific CPU group. Could you please tell me the cause and solution for this?

All cpu's cpuinfo_min_freq and cpuinfo_max_freq are (1500, 2000). Also, the scaling driver is acpi-cpufreq, and the policy is ondemand.

0-63,128-191 CPUs clock speed shows 1500MHz, but others show 400MHz even if we use them 100% usage.

admin@ubuntu ~ % cpufreq-info | grep CPU | less
analyzing CPU 0:
  CPUs which run at the same hardware frequency: 0
  CPUs which need to have their frequency coordinated by software: 0
  current CPU frequency is 1.50 GHz.
...
analyzing CPU 64:
  CPUs which run at the same hardware frequency: 64
  CPUs which need to have their frequency coordinated by software: 64
  current CPU frequency is 399 MHz.

But when I print cpufreq from hardware, they all show 1500MHz.

sudo cpufreq-info | grep CPU | less
analyzing CPU 0:
  CPUs which run at the same hardware frequency: 0
  CPUs which need to have their frequency coordinated by software: 0
  current CPU frequency is 1.50 GHz (asserted by call to hardware).
analyzing CPU 64:
  CPUs which run at the same hardware frequency: 64
  CPUs which need to have their frequency coordinated by software: 64
  current CPU frequency is 1.50 GHz (asserted by call to hardware).

lscpu command shows that low-frequency CPUs are in NUMA node 1. Could this be related?

admin@ubuntu ~ % lscpu
Architecture:        x86_64
CPU op-mode(s):      32-bit, 64-bit
Byte Order:          Little Endian
CPU(s):              256
On-line CPU(s) list: 0-255
Thread(s) per core:  2
Core(s) per socket:  64
Socket(s):           2
NUMA node(s):        2
Vendor ID:           AuthenticAMD
CPU family:          25
Model:               1
Model name:          AMD EPYC 7713 64-Core Processor
Stepping:            1
CPU MHz:             1499.971
CPU max MHz:         2000.0000
CPU min MHz:         1500.0000
BogoMIPS:            4000.23
Virtualization:      AMD-V
L1d cache:           32K
L1i cache:           32K
L2 cache:            512K
L3 cache:            32768K
NUMA node0 CPU(s):   0-63,128-191
NUMA node1 CPU(s):   64-127,192-255
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 pcid sse4_1 sse4_2 x2apic movbe popcnt aes xsave avx f16c rdrand lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs skinit wdt tce topoext perfctr_core perfctr_nb bpext perfctr_llc mwaitx cpb cat_l3 cdp_l3 invpcid_single hw_pstate ssbd mba ibrs ibpb stibp vmmcall fsgsbase bmi1 avx2 smep bmi2 erms invpcid cqm rdt_a rdseed adx smap clflushopt clwb sha_ni xsaveopt xsavec xgetbv1 xsaves cqm_llc cqm_occup_llc cqm_mbm_total cqm_mbm_local clzero irperf xsaveerptr wbnoinvd arat npt lbrv svm_lock nrip_save tsc_scale vmcb_clean flushbyasid decodeassists pausefilter pfthreshold v_vmsave_vmload vgif umip pku ospke vaes vpclmulqdq rdpid overflow_recov succor smca

Temperature

admin@ubuntu ~ % sensors
i350bb-pci-e500
Adapter: PCI adapter
loc1:         +48.0°C  (high = +120.0°C, crit = +110.0°C)

+) When I change policy as a performance, It just affects cpuinfo_cur_freq, not scaling_cur_freq.

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