{ "kind": "HYPOTHETICAL_AMDAHL_SENSITIVITY_NOT_A_BENCHMARK", "comparison": "Existing 0.33.8 measurements (5 runs, cache off) vs measured nginx", "not_measured": "0.34.0 server performance and sendfile syscall/runtime correctness", "conditions": [ "Identical CPU and network assumptions to supplied 0.33.8 baseline", "WWW zero-copy is limited to Linux, cleartext HTTP/1.1, GET >=64KiB, no cache, range, transform, compression or TLS", "WWW low/middle/high: file-copy contributes 20%/40%/60% of total request time; modeled sendfile eliminates 50% of that component", "Reverse proxy low/middle/high: removing response-frame mutex saves a hypothetical 1%/3%/5% of total service time", "These fractions are chosen sensitivity parameters; not measured or inferred from profiling", "No change is assumed for WWW 1040B or out-of-scope protocol paths", "No network saturation, TLS record processing, queueing, origin latency, filesystem cache misses, CPU contention or concurrency effects modeled", "No additional speedup due to cache-retention changes is assumed" ], "formula": "RPS_sim = RPS_0.33.8 / (1 - fraction_of_total_service_time_eliminated)", "entries": [ { "kind": "reverse_proxy", "bytes": 1040, "baseline_version": "0.33.8", "baseline_rust_rps": 29334.12, "baseline_nginx_rps": 170610.16, "baseline_of_nginx_pct": 17.19, "factor_to_match_nginx": 5.82, "sendfile_eligible_only_if_plain_linux_http1_1_no_cache_no_compression": false, "scenarios": { "low": { "modeled_total_time_saved_pct": 1.0, "simulated_rps": 29630, "simulated_rps_gain_pct": 1.01, "simulated_of_nginx_pct": 17.37, "simulated_remaining_gap_to_nginx_pct_points": 82.63 }, "middle": { "modeled_total_time_saved_pct": 3.0, "simulated_rps": 30241, "simulated_rps_gain_pct": 3.09, "simulated_of_nginx_pct": 17.73, "simulated_remaining_gap_to_nginx_pct_points": 82.27 }, "high": { "modeled_total_time_saved_pct": 5.0, "simulated_rps": 30878, "simulated_rps_gain_pct": 5.26, "simulated_of_nginx_pct": 18.1, "simulated_remaining_gap_to_nginx_pct_points": 81.9 } } }, { "kind": "reverse_proxy", "bytes": 65536, "baseline_version": "0.33.8", "baseline_rust_rps": 20735.07, "baseline_nginx_rps": 35393.29, "baseline_of_nginx_pct": 58.58, "factor_to_match_nginx": 1.71, "sendfile_eligible_only_if_plain_linux_http1_1_no_cache_no_compression": false, "scenarios": { "low": { "modeled_total_time_saved_pct": 1.0, "simulated_rps": 20945, "simulated_rps_gain_pct": 1.01, "simulated_of_nginx_pct": 59.18, "simulated_remaining_gap_to_nginx_pct_points": 40.82 }, "middle": { "modeled_total_time_saved_pct": 3.0, "simulated_rps": 21376, "simulated_rps_gain_pct": 3.09, "simulated_of_nginx_pct": 60.4, "simulated_remaining_gap_to_nginx_pct_points": 39.6 }, "high": { "modeled_total_time_saved_pct": 5.0, "simulated_rps": 21826, "simulated_rps_gain_pct": 5.26, "simulated_of_nginx_pct": 61.67, "simulated_remaining_gap_to_nginx_pct_points": 38.33 } } }, { "kind": "reverse_proxy", "bytes": 1048576, "baseline_version": "0.33.8", "baseline_rust_rps": 4461.19, "baseline_nginx_rps": 2730.23, "baseline_of_nginx_pct": 163.4, "factor_to_match_nginx": 0.61, "sendfile_eligible_only_if_plain_linux_http1_1_no_cache_no_compression": false, "scenarios": { "low": { "modeled_total_time_saved_pct": 1.0, "simulated_rps": 4506, "simulated_rps_gain_pct": 1.01, "simulated_of_nginx_pct": 165.05, "simulated_remaining_gap_to_nginx_pct_points": -65.05 }, "middle": { "modeled_total_time_saved_pct": 3.0, "simulated_rps": 4599, "simulated_rps_gain_pct": 3.09, "simulated_of_nginx_pct": 168.45, "simulated_remaining_gap_to_nginx_pct_points": -68.45 }, "high": { "modeled_total_time_saved_pct": 5.0, "simulated_rps": 4696, "simulated_rps_gain_pct": 5.26, "simulated_of_nginx_pct": 172.0, "simulated_remaining_gap_to_nginx_pct_points": -72.0 } } }, { "kind": "www", "bytes": 1040, "baseline_version": "0.33.8", "baseline_rust_rps": 24906.2, "baseline_nginx_rps": 351605.13, "baseline_of_nginx_pct": 7.08, "factor_to_match_nginx": 14.12, "sendfile_eligible_only_if_plain_linux_http1_1_no_cache_no_compression": false, "scenarios": { "low": { "modeled_total_time_saved_pct": 0.0, "simulated_rps": 24906, "simulated_rps_gain_pct": 0.0, "simulated_of_nginx_pct": 7.08, "simulated_remaining_gap_to_nginx_pct_points": 92.92 }, "middle": { "modeled_total_time_saved_pct": 0.0, "simulated_rps": 24906, "simulated_rps_gain_pct": 0.0, "simulated_of_nginx_pct": 7.08, "simulated_remaining_gap_to_nginx_pct_points": 92.92 }, "high": { "modeled_total_time_saved_pct": 0.0, "simulated_rps": 24906, "simulated_rps_gain_pct": 0.0, "simulated_of_nginx_pct": 7.08, "simulated_remaining_gap_to_nginx_pct_points": 92.92 } } }, { "kind": "www", "bytes": 65536, "baseline_version": "0.33.8", "baseline_rust_rps": 20856.67, "baseline_nginx_rps": 203709.91, "baseline_of_nginx_pct": 10.24, "factor_to_match_nginx": 9.77, "sendfile_eligible_only_if_plain_linux_http1_1_no_cache_no_compression": true, "scenarios": { "low": { "modeled_total_time_saved_pct": 10.0, "simulated_rps": 23174, "simulated_rps_gain_pct": 11.11, "simulated_of_nginx_pct": 11.38, "simulated_remaining_gap_to_nginx_pct_points": 88.62 }, "middle": { "modeled_total_time_saved_pct": 20.0, "simulated_rps": 26071, "simulated_rps_gain_pct": 25.0, "simulated_of_nginx_pct": 12.8, "simulated_remaining_gap_to_nginx_pct_points": 87.2 }, "high": { "modeled_total_time_saved_pct": 30.0, "simulated_rps": 29795, "simulated_rps_gain_pct": 42.86, "simulated_of_nginx_pct": 14.63, "simulated_remaining_gap_to_nginx_pct_points": 85.37 } } }, { "kind": "www", "bytes": 1048576, "baseline_version": "0.33.8", "baseline_rust_rps": 2833.71, "baseline_nginx_rps": 12611.49, "baseline_of_nginx_pct": 22.47, "factor_to_match_nginx": 4.45, "sendfile_eligible_only_if_plain_linux_http1_1_no_cache_no_compression": true, "scenarios": { "low": { "modeled_total_time_saved_pct": 10.0, "simulated_rps": 3149, "simulated_rps_gain_pct": 11.11, "simulated_of_nginx_pct": 24.97, "simulated_remaining_gap_to_nginx_pct_points": 75.03 }, "middle": { "modeled_total_time_saved_pct": 20.0, "simulated_rps": 3542, "simulated_rps_gain_pct": 25.0, "simulated_of_nginx_pct": 28.09, "simulated_remaining_gap_to_nginx_pct_points": 71.91 }, "high": { "modeled_total_time_saved_pct": 30.0, "simulated_rps": 4048, "simulated_rps_gain_pct": 42.86, "simulated_of_nginx_pct": 32.1, "simulated_remaining_gap_to_nginx_pct_points": 67.9 } } } ] }