quest: pin benchmark cores and fold moq-quic into bench CI

quest/m1/quic/coverage/README.md

@@ -45,6 +45,7 @@ and the harness defaults to Cubic while production runs BBR3.
 - [Benchmarks](/quest/m1/quic/coverage/bench.md) - Criterion sweeps of stream scheduling, receive and reset, endpoint routing, and the wire codec, on the baseline
 - [Characterization tests](/quest/m1/quic/coverage/characterize.md) - golden scheduling order, and every uncovered frame, reset, limit, and endpoint path, on today's harness
 - [Seeded simulation](/quest/m1/quic/coverage/sim.md) - a deterministic, impaired network in `Pair`, BBR3 as the harness default, and property tests over random workloads
+- [Pin benchmark cores](/quest/m1/quic/coverage/bench-pin.md) - local base/head comparisons run on one core type on hybrid CPUs
 
 ## Related
 

quest/m1/quic/coverage/bench-pin.md

@@ -0,0 +1,20 @@
+# [XS] Pin local benchmark comparisons to one core type
+
+## Goal
+
+On a hybrid CPU (performance and efficiency cores), `bench/run.sh` runs
+both sides of a comparison on the same core type, so a base/head delta no
+longer depends on where the scheduler put each run. On a CPU with one core
+type nothing changes.
+
+## Plan
+
+Decided 2026-10-16 with the maintainer. Seen while landing the moq-quic
+benchmarks: on an 8P/16E host the same unpinned case measured 420 µs or
+690 µs depending on the core it ran on. Detect the performance cores where
+the kernel reports them (for example `/sys/devices/cpu_core/cpus` on Intel
+hybrid parts) and pin each benchmark process to them with `taskset`. Print
+which cores were used beside the comparison, so a reader knows the run was
+pinned.
+
+Public API: none. Wire: none.

quest/m2/bench-ci.md

@@ -39,6 +39,12 @@ a GitHub App:
   own alert disabled. The `moq-uring` socket
   benches run only here, and skip loudly when the runner's kernel is too old. Add the workflow's name to
   `alert.yml` if it isn't `Nightly`.
+- Decided 2026-10-16: moq-quic's Criterion targets (#5812) join the
+  selection. They time thread CPU rather than wall time, which already cut
+  most host noise; on a shared hybrid-core host, identical builds still
+  swing about 5% on small cases and 20-130% on large-working-set ones, so
+  the noise floor must come from A/A runs on the CI runner itself, never
+  from a laptop.
 - Validate with an A/A run (the same commit twice) and a deliberately slowed
   bench before trusting either signal.
 - Document the comment, the trend, and local reproduction in