intel-microcode and performance hit after upgrade to 7.1

[kristian]

Hi,

I'm seeking some advice on intel-microcode and significantly reduced pveperf result after upgrade to Proxmox 7.1. I just upgraded from 6.4 to 7.1.

pveperf on 6.4, intel-microcode installed:

root@pve:/# pveperf
CPU BOGOMIPS:      68264.00
REGEX/SECOND:      1284037
HD SIZE:           14.46 GB (/dev/mapper/pve-root)
BUFFERED READS:    250.92 MB/sec
AVERAGE SEEK TIME: 0.29 ms
FSYNCS/SECOND:     1359.38
DNS EXT:           15.79 ms
DNS INT:           16.80 ms (home.DOMAIN)

pveperf after upgrade to 7.1:

root@pve:~# pveperf
CPU BOGOMIPS:      68269.76
REGEX/SECOND:      421511
HD SIZE:           14.46 GB (/dev/mapper/pve-root)
BUFFERED READS:    251.28 MB/sec
AVERAGE SEEK TIME: 0.27 ms
FSYNCS/SECOND:     1309.47
DNS EXT:           40.32 ms
DNS INT:           25.14 ms (home.DOMAIN.me)

Added non-free package repository and upgraded intel-microcode, but no difference in pveperf results

root@pve:~# apt -a list --upgradable
Listing... Done
intel-microcode/stable 3.20210608.2 amd64 [upgradable from: 3.20201118.1~bpo10+1]
intel-microcode/now 3.20201118.1~bpo10+1 amd64 [installed,upgradable to: 3.20210608.2]

Then followed this to disable intel-microcode in GRUB
And apt remove intel-microcode:

root@pve:~# pveperf
CPU BOGOMIPS:      68273.76
REGEX/SECOND:      1224320
HD SIZE:           14.46 GB (/dev/mapper/pve-root)
BUFFERED READS:    250.64 MB/sec
AVERAGE SEEK TIME: 0.24 ms
FSYNCS/SECOND:     1493.69
DNS EXT:           36.46 ms
DNS INT:           25.65 ms (home.DOMAIN.me)

• What could be causing the difference in REGEX/second from 6.4 to 7.1, both with microcode installed?
• Spectre-meltdown-checker shows the same result with intel-microcode installed or not, do I not need it?

intel-microcode installed:


removed:



After removing intel-microcode:

root@pve:~# apt list --installed | grep microcode
root@pve:~# dmesg | grep microcode
[    0.903579] MDS: Vulnerable: Clear CPU buffers attempted, no microcode
[    2.487659] microcode: sig=0x206c2, pf=0x1, revision=0x1f
[    2.488913] microcode: Microcode Update Driver: v2.2.

root@pve:~# lscpu
Architecture:                    x86_64
CPU op-mode(s):                  32-bit, 64-bit
Byte Order:                      Little Endian
Address sizes:                   40 bits physical, 48 bits virtual
CPU(s):                          16
On-line CPU(s) list:             0-15
Thread(s) per core:              2
Core(s) per socket:              4
Socket(s):                       2
NUMA node(s):                    2
Vendor ID:                       GenuineIntel
CPU family:                      6
Model:                           44
Model name:                      Intel(R) Xeon(R) CPU           L5630  @ 2.13GHz
Stepping:                        2
Frequency boost:                 enabled
CPU MHz:                         1959.970
CPU max MHz:                     2134.0000
CPU min MHz:                     1600.0000
BogoMIPS:                        4267.13
Virtualization:                  VT-x
L1d cache:                       256 KiB
L1i cache:                       256 KiB
L2 cache:                        2 MiB
L3 cache:                        24 MiB
NUMA node0 CPU(s):               0-3,8-11
NUMA node1 CPU(s):               4-7,12-15
Vulnerability Itlb multihit:     KVM: Mitigation: Split huge pages
Vulnerability L1tf:              Mitigation; PTE Inversion; VMX conditional cache flushes, SMT vulnerable
Vulnerability Mds:               Vulnerable: Clear CPU buffers attempted, no microcode; SMT vulnerable
Vulnerability Meltdown:          Mitigation; PTI
Vulnerability Spec store bypass: Mitigation; Speculative Store Bypass disabled via prctl and seccomp
Vulnerability Spectre v1:        Mitigation; usercopy/swapgs barriers and __user pointer sanitization
Vulnerability Spectre v2:        Mitigation; Full generic retpoline, IBPB conditional, IBRS_FW, STIBP conditional, RSB filling
Vulnerability Srbds:             Not affected
Vulnerability Tsx async abort:   Not affected
Flags:                           fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr s
                                 se sse2 ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xto
                                 pology nonstop_tsc cpuid aperfmperf pni pclmulqdq dtes64 monitor ds_cpl vmx smx est tm2 ssse3 cx16
                                 xtpr pdcm pcid dca sse4_1 sse4_2 popcnt aes lahf_lm epb pti ssbd ibrs ibpb stibp tpr_shadow vnmi fl
                                 expriority ept vpid dtherm ida arat flush_l1d