| # 2022-08-16 Triage Log |
| |
| A fairly quiet week for performance, with the exception of the LLVM 15 upgrade |
| which resulted in many changes, mostly to the positive. |
| |
| Triage done by **@simulacrum**. |
| Revision range: [cc4dd6fc9f1a5c798df269933c7e442b79661a86..14a459bf37bc19476d43e0045d078121c12d3fef](https://perf.rust-lang.org/?start=cc4dd6fc9f1a5c798df269933c7e442b79661a86&end=14a459bf37bc19476d43e0045d078121c12d3fef&absolute=false&stat=instructions%3Au) |
| |
| **Summary**: |
| |
| | (instructions:u) | mean | max | count | |
| |:----------------:|:----:|:---:|:-----:| |
| | Regressions ❌ <br /> (primary) | 0.7% | 7.7% | 62 | |
| | Regressions ❌ <br /> (secondary) | 1.3% | 5.0% | 51 | |
| | Improvements ✅ <br /> (primary) | -1.8% | -6.9% | 93 | |
| | Improvements ✅ <br /> (secondary) | -2.4% | -22.0% | 128 | |
| | All ❌✅ (primary) | -0.8% | 7.7% | 155 | |
| |
| |
| 2 Regressions, 4 Improvements, 2 Mixed; 1 of them in rollups |
| 38 artifact comparisons made in total |
| |
| #### Regressions |
| |
| consider unnormalized types for implied bounds [#99217](https://github.com/rust-lang/rust/pull/99217) [(Comparison Link)](https://perf.rust-lang.org/compare.html?start=6d3f1beae1720055e5a30f4dbe7a9e7fb810c65e&end=63e4312e6bd50ec9859c363402209809fb8155d5&stat=instructions:u) |
| |
| | (instructions:u) | mean | max | count | |
| |:----------------:|:----:|:---:|:-----:| |
| | Regressions ❌ <br /> (primary) | 0.7% | 1.9% | 37 | |
| | Regressions ❌ <br /> (secondary) | 2.0% | 2.4% | 11 | |
| | Improvements ✅ <br /> (primary) | - | - | 0 | |
| | Improvements ✅ <br /> (secondary) | - | - | 0 | |
| | All ❌✅ (primary) | 0.7% | 1.9% | 37 | |
| |
| This regression is caused by a soundness fix. |
| [#99725](https://github.com/rust-lang/rust/pull/99725) recovered a small amount |
| of the lost performance here. |
| |
| rustdoc: Merge source code pages HTML elements together [#100429](https://github.com/rust-lang/rust/pull/100429) [(Comparison Link)](https://perf.rust-lang.org/compare.html?start=4c5665583815a0f0f3e22516441efb43ea6dede2&end=801821d1560f84e4716fcbd9244ec959320a13d5&stat=instructions:u) |
| |
| | (instructions:u) | mean | max | count | |
| |:----------------:|:----:|:---:|:-----:| |
| | Regressions ❌ <br /> (primary) | 0.6% | 1.4% | 12 | |
| | Regressions ❌ <br /> (secondary) | 1.8% | 3.1% | 8 | |
| | Improvements ✅ <br /> (primary) | - | - | 0 | |
| | Improvements ✅ <br /> (secondary) | - | - | 0 | |
| | All ❌✅ (primary) | 0.6% | 1.4% | 12 | |
| |
| The regressions are limited to doc benchmarks and the underlying change reduces |
| the number of DOM elements generated by ~30% across a few samples (see PR |
| description for details). Those sizes aren't measured by perf.rust-lang.org |
| today, so there's no reflection of that here, but the size improvement is a |
| welcome one. |
| |
| #### Improvements |
| |
| Reoptimize layout array [#99174](https://github.com/rust-lang/rust/pull/99174) [(Comparison Link)](https://perf.rust-lang.org/compare.html?start=29e4a9ee0253cd39e552a77f51f11f9a5f1c41e6&end=908fc5b26d15fc96d630ab921e70b2db77a532c4&stat=instructions:u) |
| |
| | (instructions:u) | mean | max | count | |
| |:----------------:|:----:|:---:|:-----:| |
| | Regressions ❌ <br /> (primary) | - | - | 0 | |
| | Regressions ❌ <br /> (secondary) | - | - | 0 | |
| | Improvements ✅ <br /> (primary) | -0.4% | -0.8% | 10 | |
| | Improvements ✅ <br /> (secondary) | -0.8% | -1.2% | 5 | |
| | All ❌✅ (primary) | -0.4% | -0.8% | 10 | |
| |
| |
| Remove manual implementations of HashStable for hir::Expr and hir::Ty. [#100237](https://github.com/rust-lang/rust/pull/100237) [(Comparison Link)](https://perf.rust-lang.org/compare.html?start=3694b7d307b7516757651952b30bb97b6ba5c049&end=ef9810a3e2a9a16e79176cb0d3466ea82d239942&stat=instructions:u) |
| |
| | (instructions:u) | mean | max | count | |
| |:----------------:|:----:|:---:|:-----:| |
| | Regressions ❌ <br /> (primary) | - | - | 0 | |
| | Regressions ❌ <br /> (secondary) | - | - | 0 | |
| | Improvements ✅ <br /> (primary) | -0.2% | -0.2% | 3 | |
| | Improvements ✅ <br /> (secondary) | - | - | 0 | |
| | All ❌✅ (primary) | -0.2% | -0.2% | 3 | |
| |
| Possibly spurious, but leaving in the report -- bitmaps-3.1.0 check typically does not [see] this much impact on a run to run basis so it's probably at least partially real. |
| |
| [see]: https://perf.rust-lang.org/index.html?start=2022-07-01&end=ef9810a3e2a9a16e79176cb0d3466ea82d239942&benchmark=bitmaps-3.1.0&profile=check&scenario=incr-unchanged&stat=instructions:u&kind=percentfromfirst |
| |
| |
| Shrink `ast::Attribute`. [#100441](https://github.com/rust-lang/rust/pull/100441) [(Comparison Link)](https://perf.rust-lang.org/compare.html?start=8556e6620e4866526b3cea767ad8c20ae877a569&end=14a459bf37bc19476d43e0045d078121c12d3fef&stat=instructions:u) |
| |
| | (instructions:u) | mean | max | count | |
| |:----------------:|:----:|:---:|:-----:| |
| | Regressions ❌ <br /> (primary) | 0.6% | 0.6% | 1 | |
| | Regressions ❌ <br /> (secondary) | 0.2% | 0.2% | 1 | |
| | Improvements ✅ <br /> (primary) | -0.6% | -1.4% | 22 | |
| | Improvements ✅ <br /> (secondary) | -1.0% | -1.5% | 23 | |
| | All ❌✅ (primary) | -0.5% | -1.4% | 23 | |
| |
| Mostly an improvement in doc benchmarks, though a few check benchmarks improved |
| as well. An excellent win for memory usage, with up to 5.8% wins on helloworld. |
| |
| passes: load `defined_lib_features` query less [#100328](https://github.com/rust-lang/rust/pull/100328) [(Comparison Link)](https://perf.rust-lang.org/compare.html?start=569788e47ee3595c9c6f0e332844d982b3e991c2&end=0068b8bf4b150b506ef0871be4e8652fd4308f84&stat=instructions:u) |
| |
| | (instructions:u) | mean | max | count | |
| |:----------------:|:----:|:---:|:-----:| |
| | Regressions ❌ <br /> (primary) | - | - | 0 | |
| | Regressions ❌ <br /> (secondary) | 0.8% | 1.5% | 3 | |
| | Improvements ✅ <br /> (primary) | -0.4% | -0.4% | 1 | |
| | Improvements ✅ <br /> (secondary) | -1.2% | -1.8% | 8 | |
| | All ❌✅ (primary) | -0.4% | -0.4% | 1 | |
| |
| The regressions here appear to be spurious, with performance recovering on the |
| next commit. Otherwise, this is a good improvement. |
| |
| #### Mixed |
| |
| Rollup of 13 pull requests [#100426](https://github.com/rust-lang/rust/pull/100426) [(Comparison Link)](https://perf.rust-lang.org/compare.html?start=20ffea6938b5839c390252e07940b99e3b6a889a&end=2ed0f29168f5bc116e747152be600519b5d78bfd&stat=instructions:u) |
| |
| | (instructions:u) | mean | max | count | |
| |:----------------:|:----:|:---:|:-----:| |
| | Regressions ❌ <br /> (primary) | 0.3% | 0.4% | 4 | |
| | Regressions ❌ <br /> (secondary) | 0.5% | 0.7% | 5 | |
| | Improvements ✅ <br /> (primary) | -0.9% | -0.9% | 1 | |
| | Improvements ✅ <br /> (secondary) | -1.8% | -1.8% | 1 | |
| | All ❌✅ (primary) | 0.0% | -0.9% | 5 | |
| |
| Small-ish regression narrowed down to |
| [#99337](https://github.com/rust-lang/rust/pull/99337), some active work in |
| this area of rustdoc is likely to help here soon. |
| |
| Update to LLVM 15 [#99464](https://github.com/rust-lang/rust/pull/99464) [(Comparison Link)](https://perf.rust-lang.org/compare.html?start=b998821e4c51c44a9ebee395c91323c374236bbb&end=e2b52ff73edc8b0b7c74bc28760d618187731fe8&stat=instructions:u) |
| |
| | (instructions:u) | mean | max | count | |
| |:----------------:|:----:|:---:|:-----:| |
| | Regressions ❌ <br /> (primary) | 0.8% | 7.5% | 40 | |
| | Regressions ❌ <br /> (secondary) | 1.2% | 4.4% | 29 | |
| | Improvements ✅ <br /> (primary) | -1.5% | -6.0% | 100 | |
| | Improvements ✅ <br /> (secondary) | -2.6% | -21.6% | 94 | |
| | All ❌✅ (primary) | -0.9% | 7.5% | 140 | |
| |
| Overall the benefits here outweigh the negatives, with a number of good |
| improvements. LLVM upgrades are something we're going to keep rolling forward |
| on regardless. For wall time metrics the improvement here looks particularly |
| nice, with bootstrap times improved by ~4%, shaving 30 seconds of the total |
| time measured by perf. |
| |
