Results.rst

Benchmark results

All benchmarks were executed using bench_zfex binary compiled for a given target. Executions were performed using attached scripts, legacy_zfec.sh and zfex.sh.

Between different runs, results which had lowest difference between best and worst values were selected and mean value was used.

Intel x64

This benchmark was run on virtualized instance of Intel(R) Xeon(R), clocked at 2.2 GHz.

Architecture:                    x86_64
CPU op-mode(s):                  32-bit, 64-bit
Byte Order:                      Little Endian
Address sizes:                   46 bits physical, 48 bits virtual
CPU(s):                          4
On-line CPU(s) list:             0-3
Thread(s) per core:              2
Core(s) per socket:              2
Socket(s):                       1
NUMA node(s):                    1
Vendor ID:                       GenuineIntel
CPU family:                      6
Model:                           79
Model name:                      Intel(R) Xeon(R) CPU @ 2.20GHz
Stepping:                        0
CPU MHz:                         2200.222
BogoMIPS:                        4400.44
Hypervisor vendor:               KVM
Virtualization type:             full
L1d cache:                       64 KiB
L1i cache:                       64 KiB
L2 cache:                        512 KiB
L3 cache:                        55 MiB
NUMA node0 CPU(s):               0-3
Vulnerability Itlb multihit:     Not affected
Vulnerability L1tf:              Mitigation; PTE Inversion
Vulnerability Mds:               Mitigation; Clear CPU buffers; SMT Host state unknown
Vulnerability Meltdown:          Mitigation; PTI
Vulnerability Mmio stale data:   Vulnerable: Clear CPU buffers attempted, no microcode; SMT Host state unknown
Vulnerability Retbleed:          Mitigation; IBRS
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; IBRS, IBPB conditional, RSB filling
Vulnerability Srbds:             Not affected
Vulnerability Tsx async abort:   Mitigation; Clear CPU buffers; SMT Host state unknown
Flags:                           fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ss ht syscall nx pdpe1gb rdtscp lm constant_tsc rep_good nopl xtopology nonstop_tsc cpuid tsc_known_freq pni pclmulqdq ssse3 fma cx16 pcid sse4_1 sse4_2 x2apic movbe popcnt aes xsave avx f16c rdrand hypervisor lahf_lm abm 3dnowprefetch invpcid_single pti ssbd ibrs ibpb stibp fsgsbase tsc_adjust bmi1 hle avx2 smep bmi2 erms invpcid rtm rdseed adx smap xsaveopt arat md_clear arch_capabilities

Compiler used was:

gcc (Ubuntu 9.4.0-1ubuntu1~20.04.1) 9.4.0

For legacy zfec two results were picked, one for code compiled with -O2 optimization, which is very likely binary code packaged with precompiled wheel packages, and the other one compiled with -O3 -march=native flags, which gave the best results.

zfex benchmark was run for fec_encode_simd in five different configurations, one with -O2 optimization and the other ones with -O3 optimization. On top of that different variants of unrolling parameters were set.

k=7 m=10 size=1000000

Legacy zfec had both results just below 600 MB/sec. zfex in all cases ran faster, achieving best performance with -DZFEX_UNROLL_ADDMUL_SIMD=8 unrolling, running over 6 times faster at ~3800 MB/sec.

k=223 m=255 size=43488

Legacy zfec had both results slightly above 50 MB/sec. zfex in all cases ran faster, achieving best performance with -DZFEX_UNROLL_ADDMUL_SIMD=4 unrolling, giving almost 6-fold speed-up.