From 4d745abf6bba02a1f63b8ed399907a7e8d08e288 Mon Sep 17 00:00:00 2001 From: Transaction Science Date: Thu, 15 Oct 2026 01:06:15 -0400 Subject: [PATCH] eoc-meter: say where the sampler-re-reads property is actually pinned The GPU-freshness report left a comment explaining why a rise the oracle saw is not one the probe must have seen. It did not say what still covers the property that assertion was reaching for, so the obvious next reader restores a hardware assertion and reintroduces the flake. It is covered deterministically, per sample, by the scripted probes: `probe_with_a_single_batch_jump_is_frozen` drives `GPU Energy` to a different value at every sample and asserts each one is exactly what the rule was handed, and `probe_with_one_die_live_and_one_frozen_is_frozen` does the same. A sampler that cached one reading fails those on sample 1, on every host, with no dependence on what the hardware happens to do. So the earlier claim that the report gave up that coverage was wrong: it gave up nothing, and driving GPU work inside the probe's window to restore a hardware assertion is unnecessary. The comment now says so, and says why no sound hardware witness exists on the CI host anyway -- its CPU rails are frozen and its GPU rail is activity-driven. Comment only; no behaviour change. Co-Authored-By: Claude Opus 5 --- eoc/eoc-rs/crates/eoc-meter/src/lib.rs | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/eoc/eoc-rs/crates/eoc-meter/src/lib.rs b/eoc/eoc-rs/crates/eoc-meter/src/lib.rs index 148188e97..7c5c9c351 100644 --- a/eoc/eoc-rs/crates/eoc-meter/src/lib.rs +++ b/eoc/eoc-rs/crates/eoc-meter/src/lib.rs @@ -3401,6 +3401,18 @@ mod macos_ioreport { // inside it. One value here is therefore no evidence of a sampler that // does not sample, and asserting it was a rise the probe must also see // failed once in ~300 CI runs on an otherwise green tree. + // + // Nothing is lost by not asserting it here: that the sampler re-reads + // is already pinned deterministically, per sample, by the scripted + // probes -- `probe_with_a_single_batch_jump_is_frozen` drives + // `GPU Energy` to a different value at every sample and asserts each + // one is what the rule was handed, as does + // `probe_with_one_die_live_and_one_frozen_is_frozen`. A sampler that + // cached one reading fails those on sample 1, on every host. So do + // not restore a hardware assertion here believing this is uncovered: + // no rail on the CI host reliably moves inside the probe's window + // (its CPU rails are frozen), so there is no sound hardware witness + // to assert on. lines.push(if values.len() >= 2 { format!("{}: moved {lo} -> {hi}, the probe read {} distinct values within it", key.0, values.len()) } else { -- 2.54.0 (Apple Git-157)