From 343e53e17b6b724803c4e7e81560c421c5a1bb49 Mon Sep 17 00:00:00 2001
From: claude-asm-audit <claude@session.local>
Date: Sat, 15 Aug 2026 17:41:32 +0000
Subject: [PATCH] bench: baseline under the fixed rq-mpmc default (job
 6e71e9b1)
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20-core box (taskset 0-19), 5 sets, at 0438f12. Replaces the rq-mutex
baseline (df41ff3) so sweep.py regress compares like with like. The
multi-thread rows show what the mutex contention was costing:
yield_many 20T 156.7ms -> 44.1ms (-72%), spawn_storm_busy 20T -72%,
chained_spawn/catch_unwind 20T -20%. Sweep ran clean (0 panics) —
the finding-13 fix holding under the full suite.
Note: mpsc_contention 1T is ~2x the mutex-default row (3155 -> 6123);
backend characteristic to investigate, not a fix regression (the
shootout shows the fix itself is noise-neutral).
---
 benches/baseline.json | 280 +++++++++++++++++++++---------------------
 1 file changed, 140 insertions(+), 140 deletions(-)

diff --git a/benches/baseline.json b/benches/baseline.json
index 8711741..e03bf6c 100644
--- a/benches/baseline.json
+++ b/benches/baseline.json
@@ -2,313 +2,313 @@
   "chained_spawn": {
     "smarm 1-thread": {
       "result": 1000,
-      "median": 496,
-      "min": 482,
-      "max": 549
+      "median": 466,
+      "min": 420,
+      "max": 503
     },
     "smarm 20-thread": {
       "result": 1000,
-      "median": 2594,
-      "min": 2527,
-      "max": 2872
+      "median": 2087,
+      "min": 1966,
+      "max": 2462
     },
     "tokio current_thread": {
       "result": 1000,
       "median": 108,
-      "min": 103,
-      "max": 113
+      "min": 101,
+      "max": 119
     },
     "tokio multi-thread": {
       "result": 1000,
-      "median": 184,
-      "min": 172,
-      "max": 204
+      "median": 185,
+      "min": 162,
+      "max": 196
     }
   },
   "yield_many": {
     "smarm 1-thread": {
       "result": 200000,
-      "median": 15092,
-      "min": 14786,
-      "max": 16512
+      "median": 12513,
+      "min": 11098,
+      "max": 12846
     },
     "smarm 20-thread": {
       "result": 200000,
-      "median": 156695,
-      "min": 155256,
-      "max": 157172
+      "median": 44080,
+      "min": 43502,
+      "max": 44754
     },
     "tokio current_thread": {
       "result": 200000,
-      "median": 4900,
-      "min": 4855,
-      "max": 5258
+      "median": 5378,
+      "min": 4781,
+      "max": 5612
     },
     "tokio multi-thread": {
       "result": 200000,
-      "median": 5547,
-      "min": 5155,
-      "max": 6367
+      "median": 6096,
+      "min": 5424,
+      "max": 7701
     }
   },
   "fan_out_compute": {
     "smarm 1-thread": {
       "result": 33860,
-      "median": 13448,
-      "min": 13408,
-      "max": 13526
+      "median": 15121,
+      "min": 13878,
+      "max": 15143
     },
     "smarm 20-thread": {
       "result": 33860,
-      "median": 2537,
-      "min": 2496,
-      "max": 2571
+      "median": 2452,
+      "min": 2389,
+      "max": 2833
     },
     "tokio current_thread": {
       "result": 33860,
-      "median": 12519,
-      "min": 12458,
-      "max": 14082
+      "median": 14113,
+      "min": 12681,
+      "max": 14123
     },
     "tokio multi-thread": {
       "result": 33860,
-      "median": 2581,
-      "min": 2418,
-      "max": 2905
+      "median": 2308,
+      "min": 1724,
+      "max": 2575
     }
   },
   "ping_pong_oneshot": {
     "smarm 1-thread": {
       "result": 1000,
-      "median": 893,
-      "min": 871,
-      "max": 934
+      "median": 839,
+      "min": 755,
+      "max": 861
     },
     "smarm 20-thread": {
       "result": 1000,
-      "median": 8185,
-      "min": 8139,
-      "max": 8771
+      "median": 7437,
+      "min": 7278,
+      "max": 8044
     },
     "tokio current_thread": {
       "result": 1000,
-      "median": 417,
-      "min": 368,
-      "max": 424
+      "median": 416,
+      "min": 399,
+      "max": 430
     },
     "tokio multi-thread": {
       "result": 1000,
-      "median": 9125,
-      "min": 8907,
-      "max": 9308
+      "median": 8963,
+      "min": 8918,
+      "max": 10302
     }
   },
   "spawn_storm_busy": {
     "smarm 1-thread": {
       "result": 10000,
-      "median": 109341,
-      "min": 97632,
-      "max": 110070
+      "median": 109585,
+      "min": 103839,
+      "max": 116230
     },
     "smarm 20-thread": {
       "result": 10000,
-      "median": 55586,
-      "min": 54366,
-      "max": 57962
+      "median": 15582,
+      "min": 15229,
+      "max": 17187
     },
     "tokio current_thread": {
       "result": 10000,
-      "median": 1256,
-      "min": 1251,
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+      "median": 1072,
+      "min": 979,
+      "max": 1106
     },
     "tokio multi-thread": {
       "result": 10000,
-      "median": 12535,
-      "min": 10858,
-      "max": 18835
+      "median": 11858,
+      "min": 11074,
+      "max": 13463
     }
   },
   "mpsc_contention": {
     "smarm 1-thread": {
       "result": 320000,
-      "median": 3155,
-      "min": 2996,
-      "max": 3370
+      "median": 6123,
+      "min": 6084,
+      "max": 6830
     },
     "smarm 20-thread": {
       "result": 320000,
-      "median": 35418,
-      "min": 35346,
-      "max": 36238
+      "median": 35813,
+      "min": 34901,
+      "max": 36057
     },
     "tokio current_thread": {
       "result": 320000,
-      "median": 5376,
-      "min": 5373,
-      "max": 5990
+      "median": 5428,
+      "min": 5388,
+      "max": 6025
     },
     "tokio multi-thread": {
       "result": 320000,
-      "median": 67180,
-      "min": 65594,
-      "max": 82199
+      "median": 67484,
+      "min": 50512,
+      "max": 74416
     }
   },
   "many_timers": {
     "smarm 1-thread": {
       "result": 10000,
-      "median": 124040,
-      "min": 114046,
-      "max": 124642
+      "median": 123609,
+      "min": 114597,
+      "max": 124898
     },
     "smarm 20-thread": {
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-      "median": 56944,
-      "min": 56510,
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+      "min": 53552,
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     "tokio current_thread": {
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     },
     "tokio multi-thread": {
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-      "median": 13872,
-      "min": 13458,
-      "max": 14706
+      "median": 14004,
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     }
   },
   "multi_thread_scaling": {
     "smarm 1-thread": {
       "result": 33860,
-      "median": 15094,
-      "min": 15091,
-      "max": 15109
+      "median": 15117,
+      "min": 15083,
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     },
     "smarm 2-thread": {
       "result": 33860,
-      "median": 7943,
-      "min": 7916,
-      "max": 8018
+      "median": 7988,
+      "min": 7911,
+      "max": 8031
     },
     "smarm 4-thread": {
       "result": 33860,
-      "median": 4293,
-      "min": 4288,
-      "max": 4407
+      "median": 4302,
+      "min": 4275,
+      "max": 4311
     },
     "smarm 20-thread": {
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-      "median": 2467,
-      "min": 2414,
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+      "median": 2413,
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     "tokio multi 1-thread": {
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+      "min": 14259,
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     "tokio multi 2-thread": {
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     "tokio multi 4-thread": {
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+      "max": 4078
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     "tokio multi 20-thread": {
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-      "median": 2374,
-      "min": 1901,
-      "max": 2453
+      "median": 2381,
+      "min": 1935,
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     }
   },
   "deep_recursion": {
     "smarm 1-thread": {
       "result": 1,
-      "median": 302,
-      "min": 297,
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+      "median": 293,
+      "min": 286,
+      "max": 322
     },
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       "result": 1,
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-      "min": 620,
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     "tokio current_thread": {
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     },
     "tokio multi-thread": {
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       "median": 54,
-      "min": 52,
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+      "min": 50,
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     }
   },
   "yield_in_hot_loop": {
     "smarm 1-thread": {
       "result": 1000000,
-      "median": 49756,
-      "min": 49387,
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+      "median": 40171,
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     "tokio current_thread": {
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+      "median": 63828,
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   },
   "uncontended_channel": {
     "smarm 1-thread": {
       "result": 1000000,
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   },
   "catch_unwind_panics": {
     "smarm 1-thread": {
       "result": 10000,
-      "median": 126620,
-      "min": 121079,
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+      "median": 127342,
+      "min": 122307,
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     "smarm 20-thread": {
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     "tokio current_thread": {
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+      "median": 2500,
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   }
 }
\ No newline at end of file