diff --git a/triage/2025/2025-07-28.md b/triage/2025/2025-07-28.md new file mode 100644 index 000000000..9b617e6a7 --- /dev/null +++ b/triage/2025/2025-07-28.md @@ -0,0 +1,191 @@ +# 2025-07-28 Triage Log + +A week with lots of mixed results, including a few benchmarks that appear to be +newly bimodal, which made some of the results look closer to noise than signal. +Overall, however, the week ended as a slight improvement. + +Triage done by **@simulacrum**. +Revision range: [3f9f20f7..e3514bde](https://perf.rust-lang.org/?start=3f9f20f71dd945fe7d044e274094a53c90788269&end=e3514bde96d2d13586337a48db77fa64b850d249&absolute=false&stat=instructions%3Au) + +**Summary**: + +| (instructions:u) | mean | range | count | +|:----------------------------------:|:-----:|:---------------:|:-----:| +| Regressions ❌
(primary) | 0.5% | [0.2%, 0.9%] | 7 | +| Regressions ❌
(secondary) | 0.4% | [0.0%, 0.7%] | 26 | +| Improvements ✅
(primary) | -0.4% | [-1.1%, -0.2%] | 69 | +| Improvements ✅
(secondary) | -1.8% | [-10.3%, -0.0%] | 96 | +| All ❌✅ (primary) | -0.3% | [-1.1%, 0.9%] | 76 | + +1 Regressions, 2 Improvements, 9 Mixed; 2 of them in rollups +38 artifact comparisons made in total + +#### Regressions + +resolve: Make disambiguators for underscore bindings module-local (take 2) [#144272](https://github.com/rust-lang/rust/pull/144272) [(Comparison Link)](https://perf.rust-lang.org/compare.html?start=3c30dbbe31bfbf6029f4534170165ba573ff0fd1&end=fc5af1813307d25a84d633f21e2e53c9376eb547&stat=instructions:u) + +| (instructions:u) | mean | range | count | +|:----------------------------------:|:----:|:------------:|:-----:| +| Regressions ❌
(primary) | 0.4% | [0.1%, 0.7%] | 17 | +| Regressions ❌
(secondary) | 0.3% | [0.0%, 0.6%] | 21 | +| Improvements ✅
(primary) | - | - | 0 | +| Improvements ✅
(secondary) | - | - | 0 | +| All ❌✅ (primary) | 0.4% | [0.1%, 0.7%] | 17 | + +Unclear root cause; cachegrind diffs point at the regression ocurring in an +unrelated function. It may also be bimodality as the regression temporarily +self-resolves in a subsequent commmit. + +#### Improvements + +Various refactors to the LTO handling code (part 2) [#144062](https://github.com/rust-lang/rust/pull/144062) [(Comparison Link)](https://perf.rust-lang.org/compare.html?start=fc5af1813307d25a84d633f21e2e53c9376eb547&end=5d22242a3a84a55be2f648a94eecff58887547f4&stat=instructions:u) + +| (instructions:u) | mean | range | count | +|:----------------------------------:|:-----:|:--------------:|:-----:| +| Regressions ❌
(primary) | - | - | 0 | +| Regressions ❌
(secondary) | - | - | 0 | +| Improvements ✅
(primary) | - | - | 0 | +| Improvements ✅
(secondary) | -3.4% | [-6.7%, -1.1%] | 6 | +| All ❌✅ (primary) | - | - | 0 | + +Avoids doing some work unless LTO is actually requested, which seems to lead to a nice improvement in the large workspace benchmark. + +Do not run per-module late lints if they can be all skipped [#139597](https://github.com/rust-lang/rust/pull/139597) [(Comparison Link)](https://perf.rust-lang.org/compare.html?start=0dd07bd2165db70ffbe0b903635de26ca630bf20&end=f32b23204a0efe2fe8383ed4be1a30b56c1bbf94&stat=instructions:u) + +| (instructions:u) | mean | range | count | +|:----------------------------------:|:-----:|:--------------:|:-----:| +| Regressions ❌
(primary) | - | - | 0 | +| Regressions ❌
(secondary) | 0.1% | [0.1%, 0.1%] | 4 | +| Improvements ✅
(primary) | -0.4% | [-0.5%, -0.2%] | 17 | +| Improvements ✅
(secondary) | -0.5% | [-1.5%, -0.1%] | 24 | +| All ❌✅ (primary) | -0.4% | [-0.5%, -0.2%] | 17 | + + +#### Mixed + +Ports `#[macro_use]` and `#[macro_escape]` to the new attribute parsing infrastructure [#143843](https://github.com/rust-lang/rust/pull/143843) [(Comparison Link)](https://perf.rust-lang.org/compare.html?start=5a30e4307f0506bed87eeecd171f8366fdbda1dc&end=4ff3fa01cbdd468851b1b859541ee1c648cde7de&stat=instructions:u) + +| (instructions:u) | mean | range | count | +|:----------------------------------:|:-----:|:--------------:|:-----:| +| Regressions ❌
(primary) | - | - | 0 | +| Regressions ❌
(secondary) | 0.2% | [0.2%, 0.2%] | 7 | +| Improvements ✅
(primary) | - | - | 0 | +| Improvements ✅
(secondary) | -0.6% | [-0.9%, -0.0%] | 4 | +| All ❌✅ (primary) | - | - | 0 | + +Not particularly worried about the regressions here, they affect +unused-warnings and deep-vector only (and not too high in magnitude) and this +is part of larger changes throughout the compiler. + +Create an `AllocId` for `ConstValue::Slice`. [#116707](https://github.com/rust-lang/rust/pull/116707) [(Comparison Link)](https://perf.rust-lang.org/compare.html?start=efd420c770bb179537c01063e98cb6990c439654&end=3c30dbbe31bfbf6029f4534170165ba573ff0fd1&stat=instructions:u) + +| (instructions:u) | mean | range | count | +|:----------------------------------:|:-----:|:---------------:|:-----:| +| Regressions ❌
(primary) | 0.7% | [0.2%, 1.0%] | 6 | +| Regressions ❌
(secondary) | 0.3% | [0.0%, 0.9%] | 38 | +| Improvements ✅
(primary) | -0.3% | [-0.6%, -0.1%] | 17 | +| Improvements ✅
(secondary) | -1.9% | [-10.2%, -0.0%] | 56 | +| All ❌✅ (primary) | -0.1% | [-0.6%, 1.0%] | 23 | + +Overall an improvement and potentially will allow for further simplifications +(https://github.com/rust-lang/rust/pull/116707#issuecomment-3069572150). + +Rollup of 15 pull requests [#144398](https://github.com/rust-lang/rust/pull/144398) [(Comparison Link)](https://perf.rust-lang.org/compare.html?start=5d22242a3a84a55be2f648a94eecff58887547f4&end=246733a3d978de41c5b77b8120ba8f41592df9f1&stat=instructions:u) + +| (instructions:u) | mean | range | count | +|:----------------------------------:|:-----:|:--------------:|:-----:| +| Regressions ❌
(primary) | 0.3% | [0.2%, 0.4%] | 3 | +| Regressions ❌
(secondary) | 0.2% | [0.0%, 0.2%] | 3 | +| Improvements ✅
(primary) | -0.4% | [-0.8%, -0.1%] | 14 | +| Improvements ✅
(secondary) | -0.3% | [-0.6%, -0.1%] | 21 | +| All ❌✅ (primary) | -0.3% | [-0.8%, 0.4%] | 17 | + +Regressions appear limited to incr-println-like scenarios most likely from +https://github.com/rust-lang/rust/pull/143374#issuecomment-3037244091. Not +worth further investigation given limited impact and the change looks fairly +benign. + +MIR-build: No longer emit assumes in enum-as casting [#144389](https://github.com/rust-lang/rust/pull/144389) [(Comparison Link)](https://perf.rust-lang.org/compare.html?start=246733a3d978de41c5b77b8120ba8f41592df9f1&end=b56aaec52bc0fa35591a872fb4aac81f606e265c&stat=instructions:u) + +| (instructions:u) | mean | range | count | +|:----------------------------------:|:-----:|:--------------:|:-----:| +| Regressions ❌
(primary) | 0.5% | [0.2%, 0.7%] | 13 | +| Regressions ❌
(secondary) | 0.3% | [0.1%, 0.6%] | 17 | +| Improvements ✅
(primary) | -0.4% | [-0.9%, -0.1%] | 8 | +| Improvements ✅
(secondary) | -0.3% | [-0.3%, -0.3%] | 1 | +| All ❌✅ (primary) | 0.1% | [-0.9%, 0.7%] | 21 | + +> looks like html5ever has gone bimodal + +(https://github.com/rust-lang/rust/pull/144389#issuecomment-3116885962) + +Resolve: refactor `define` into `define_local` and `define_extern` [#143884](https://github.com/rust-lang/rust/pull/143884) [(Comparison Link)](https://perf.rust-lang.org/compare.html?start=eed187cfce988dd669b7d9161f324433e64358ee&end=edc3841c5d28e0f54c6d3c7e906ad083129f3903&stat=instructions:u) + +| (instructions:u) | mean | range | count | +|:----------------------------------:|:-----:|:--------------:|:-----:| +| Regressions ❌
(primary) | 0.1% | [0.1%, 0.1%] | 3 | +| Regressions ❌
(secondary) | 0.5% | [0.3%, 0.7%] | 5 | +| Improvements ✅
(primary) | -0.5% | [-0.8%, -0.2%] | 15 | +| Improvements ✅
(secondary) | -0.3% | [-0.5%, -0.2%] | 27 | +| All ❌✅ (primary) | -0.4% | [-0.8%, 0.1%] | 18 | + +Overall positive, few regressions look like they might be within bimodality +thresholds. + +Avoid unnecessary `new_adt`/`new_fn_def` calls. [#144425](https://github.com/rust-lang/rust/pull/144425) [(Comparison Link)](https://perf.rust-lang.org/compare.html?start=edc3841c5d28e0f54c6d3c7e906ad083129f3903&end=4b596bbd847672da87763b76171687d3544863c2&stat=instructions:u) + +| (instructions:u) | mean | range | count | +|:----------------------------------:|:-----:|:--------------:|:-----:| +| Regressions ❌
(primary) | 0.4% | [0.4%, 0.5%] | 6 | +| Regressions ❌
(secondary) | 0.5% | [0.3%, 0.7%] | 9 | +| Improvements ✅
(primary) | -0.3% | [-0.5%, -0.1%] | 46 | +| Improvements ✅
(secondary) | -0.7% | [-1.6%, -0.1%] | 44 | +| All ❌✅ (primary) | -0.2% | [-0.5%, 0.5%] | 52 | + +Overall positive, few regressions look like they might be within bimodality +thresholds. + +Preintern some `TyKind::Bound` values [#144434](https://github.com/rust-lang/rust/pull/144434) [(Comparison Link)](https://perf.rust-lang.org/compare.html?start=4b596bbd847672da87763b76171687d3544863c2&end=f8e355c230c6eb7b78ffce6a92fd81f78c890524&stat=instructions:u) + +| (instructions:u) | mean | range | count | +|:----------------------------------:|:-----:|:--------------:|:-----:| +| Regressions ❌
(primary) | 0.1% | [0.1%, 0.1%] | 1 | +| Regressions ❌
(secondary) | 0.8% | [0.3%, 1.0%] | 8 | +| Improvements ✅
(primary) | -0.3% | [-0.4%, -0.1%] | 4 | +| Improvements ✅
(secondary) | -0.9% | [-1.7%, -0.2%] | 23 | +| All ❌✅ (primary) | -0.2% | [-0.4%, 0.1%] | 5 | + +match-stress regression looks plausibly like bimodality to me. ucd and +unicode-normalization look more real but are small in magnitude and limited in +which scenarios are affected; overall the change remains positive, so marking +as triaged. + +Rollup of 6 pull requests [#144556](https://github.com/rust-lang/rust/pull/144556) [(Comparison Link)](https://perf.rust-lang.org/compare.html?start=2b5e239c6b86cde974b0ef0f8e23754fb08ff3c5&end=733dab558992d902d6d17576de1da768094e2cf3&stat=instructions:u) + +| (instructions:u) | mean | range | count | +|:----------------------------------:|:-----:|:--------------:|:-----:| +| Regressions ❌
(primary) | - | - | 0 | +| Regressions ❌
(secondary) | 0.6% | [0.2%, 1.2%] | 6 | +| Improvements ✅
(primary) | - | - | 0 | +| Improvements ✅
(secondary) | -0.7% | [-1.0%, -0.0%] | 8 | +| All ❌✅ (primary) | - | - | 0 | + +> So that's probably #143607. One secondary proc-macro benchmark with +> regressions, another one with gains. I guess the magnitude evens out... +> +> I haven't dived into the regression yet but it's probably caused by #143940 (attributes are parsed twice). + +Marked as triaged. + +Allow more MIR SROA [#144543](https://github.com/rust-lang/rust/pull/144543) [(Comparison Link)](https://perf.rust-lang.org/compare.html?start=65b6cdb6a6d33987b9d642a4882283c71fbe3957&end=9ba00e0f9e00990fb88c1beac7172afe93b15609&stat=instructions:u) + +| (instructions:u) | mean | range | count | +|:----------------------------------:|:-----:|:--------------:|:-----:| +| Regressions ❌
(primary) | 0.5% | [0.2%, 0.8%] | 3 | +| Regressions ❌
(secondary) | 0.3% | [0.2%, 0.3%] | 6 | +| Improvements ✅
(primary) | -0.4% | [-0.6%, -0.2%] | 3 | +| Improvements ✅
(secondary) | -0.9% | [-1.0%, -0.9%] | 6 | +| All ❌✅ (primary) | 0.0% | [-0.6%, 0.8%] | 6 | + +Changes look possibly like longer-term bimodality? But this is also a MIR +optimization, so mixed results are somewhat expected.