@Mark.Shannon I had seen some speedup on tornado benchmark when I didn't use PGO+LTO. but it was noise.

Now I use PGO+LTO. master vs PR-22909:

$ ./python -m pyperf compare_to master-opt.json speedup_kw-opt.json -G --min-speed=1
Slower (11):
- spectral_norm: 147 ms +- 1 ms -> 153 ms +- 2 ms: 1.04x slower (+4%)
- pickle_dict: 28.6 us +- 0.1 us -> 29.5 us +- 0.6 us: 1.03x slower (+3%)
- regex_compile: 199 ms +- 1 ms -> 204 ms +- 4 ms: 1.03x slower (+3%)
- chameleon: 9.75 ms +- 0.10 ms -> 9.99 ms +- 0.09 ms: 1.02x slower (+2%)
- logging_format: 10.9 us +- 0.2 us -> 11.1 us +- 0.2 us: 1.02x slower (+2%)
- sqlite_synth: 3.29 us +- 0.05 us -> 3.36 us +- 0.05 us: 1.02x slower (+2%)
- regex_v8: 26.1 ms +- 0.1 ms -> 26.5 ms +- 0.3 ms: 1.02x slower (+2%)
- json_dumps: 14.6 ms +- 0.1 ms -> 14.8 ms +- 0.1 ms: 1.02x slower (+2%)
- logging_simple: 9.88 us +- 0.18 us -> 10.0 us +- 0.2 us: 1.02x slower (+2%)
- nqueens: 105 ms +- 1 ms -> 107 ms +- 2 ms: 1.01x slower (+1%)
- raytrace: 511 ms +- 5 ms -> 517 ms +- 6 ms: 1.01x slower (+1%)

Faster (10):
- regex_dna: 233 ms +- 1 ms -> 229 ms +- 1 ms: 1.02x faster (-2%)
- unpickle: 14.7 us +- 0.1 us -> 14.5 us +- 0.2 us: 1.02x faster (-1%)
- deltablue: 8.17 ms +- 0.29 ms -> 8.06 ms +- 0.17 ms: 1.01x faster (-1%)
- mako: 16.8 ms +- 0.2 ms -> 16.6 ms +- 0.1 ms: 1.01x faster (-1%)
- xml_etree_iterparse: 117 ms +- 1 ms -> 116 ms +- 1 ms: 1.01x faster (-1%)
- scimark_monte_carlo: 117 ms +- 2 ms -> 115 ms +- 1 ms: 1.01x faster (-1%)
- xml_etree_parse: 164 ms +- 3 ms -> 162 ms +- 1 ms: 1.01x faster (-1%)
- unpack_sequence: 62.7 ns +- 0.7 ns -> 62.0 ns +- 0.7 ns: 1.01x faster (-1%)
- regex_effbot: 3.43 ms +- 0.01 ms -> 3.39 ms +- 0.02 ms: 1.01x faster (-1%)
- scimark_fft: 405 ms +- 4 ms -> 401 ms +- 1 ms: 1.01x faster (-1%)

Benchmark hidden because not significant (39)