Skip to content
Merged
Changes from 1 commit
Commits
File filter

Filter by extension

Filter by extension

Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
144 changes: 144 additions & 0 deletions triage/2026/2026-02-02.md
Original file line number Diff line number Diff line change
@@ -0,0 +1,144 @@
# 2026-02-02 Triage Log

Overall a positive week for instruction counts (~1% improvement on
check/debug/opt/doc builds). Cycle counts and memory usage remain broadly
unchanged across the week though.

Triage done by **@simulacrum**.
Revision range: [ebf13cca..a60d12cb](https://perf.rust-lang.org/?start=ebf13cca58b551b83133d4895e123f7d1e795111&end=a60d12cbccfbeaf153f3cecb90454aa696ea4b3b&absolute=false&stat=instructions%3Au)

**Summary**:

| (instructions:u) | mean | range | count |
|:----------------------------------:|:-----:|:---------------:|:-----:|
| Regressions ❌ <br /> (primary) | 2.7% | [0.3%, 7.3%] | 3 |
| Regressions ❌ <br /> (secondary) | 3.2% | [0.3%, 6.0%] | 2 |
| Improvements ✅ <br /> (primary) | -1.2% | [-3.2%, -0.2%] | 243 |
| Improvements ✅ <br /> (secondary) | -1.4% | [-10.2%, -0.2%] | 301 |
| All ❌✅ (primary) | -1.2% | [-3.2%, 7.3%] | 246 |
Copy link
Contributor

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

That's a good week!


0 Regression, 6 Improvements, 3 Mixed; 3 of them in rollups
33 artifact comparisons made in total

#### Regressions

No regressions this week.

#### Improvements

Rollup of 8 pull requests [#151835](https://github.com/rust-lang/rust/pull/151835) [(Comparison Link)](https://perf.rust-lang.org/compare.html?start=370143facfb348ad3b29749c0393402d76b280c3&end=842bd5be253e17831e318fdbd9d01d716557cc75&stat=instructions:u)

| (instructions:u) | mean | range | count |
|:----------------------------------:|:-----:|:--------------:|:-----:|
| Regressions ❌ <br /> (primary) | - | - | 0 |
| Regressions ❌ <br /> (secondary) | - | - | 0 |
| Improvements ✅ <br /> (primary) | -0.2% | [-0.3%, -0.2%] | 4 |
| Improvements ✅ <br /> (secondary) | -0.7% | [-1.1%, -0.2%] | 6 |
| All ❌✅ (primary) | -0.2% | [-0.3%, -0.2%] | 4 |

Small improvement on a number of benchmarks for non-incremental builds, likely
due to [#147387](https://github.com/rust-lang/rust/pull/147387) which tweaked
how `hir_owner_parent` interacts with the query system.

Pass `DepNode` by reference more places [#151881](https://github.com/rust-lang/rust/pull/151881) [(Comparison Link)](https://perf.rust-lang.org/compare.html?start=1e9be1b77fe89d9757d6179973b2fc970c6e83b7&end=271951ba187953d39b1c66b062d83f558aa23856&stat=instructions:u)

| (instructions:u) | mean | range | count |
|:----------------------------------:|:-----:|:--------------:|:-----:|
| Regressions ❌ <br /> (primary) | - | - | 0 |
| Regressions ❌ <br /> (secondary) | - | - | 0 |
| Improvements ✅ <br /> (primary) | -0.3% | [-0.4%, -0.2%] | 45 |
| Improvements ✅ <br /> (secondary) | -0.3% | [-0.3%, -0.2%] | 17 |
| All ❌✅ (primary) | -0.3% | [-0.4%, -0.2%] | 45 |


resolve: Use `IdentKey` in `resolve_ident_in_scope_set` [#151820](https://github.com/rust-lang/rust/pull/151820) [(Comparison Link)](https://perf.rust-lang.org/compare.html?start=a60d12cbccfbeaf153f3cecb90454aa696ea4b3b&end=f60a0f1bcc5a2a6dd8eb2d2021da79b40f5fbae9&stat=instructions:u)

| (instructions:u) | mean | range | count |
|:----------------------------------:|:-----:|:--------------:|:-----:|
| Regressions ❌ <br /> (primary) | - | - | 0 |
| Regressions ❌ <br /> (secondary) | - | - | 0 |
| Improvements ✅ <br /> (primary) | -0.3% | [-0.3%, -0.2%] | 8 |
| Improvements ✅ <br /> (secondary) | -0.4% | [-0.9%, -0.1%] | 22 |
| All ❌✅ (primary) | -0.3% | [-0.3%, -0.2%] | 8 |

resolve: Replace `Macros20NormalizedIdent` with `IdentKey` [#151550](https://github.com/rust-lang/rust/pull/151550) [(Comparison Link)](https://perf.rust-lang.org/compare.html?start=1e5065a4d99e0e3ccf1a1719055308e7a20e8f36&end=de6d33c033441c5880b863f94d7a3ec8cad141bd&stat=instructions:u)

| (instructions:u) | mean | range | count |
|:----------------------------------:|:-----:|:--------------:|:-----:|
| Regressions ❌ <br /> (primary) | - | - | 0 |
| Regressions ❌ <br /> (secondary) | 0.0% | [0.0%, 0.0%] | 3 |
| Improvements ✅ <br /> (primary) | -0.3% | [-0.5%, -0.1%] | 69 |
| Improvements ✅ <br /> (secondary) | -0.5% | [-1.7%, -0.0%] | 37 |
| All ❌✅ (primary) | -0.3% | [-0.5%, -0.1%] | 69 |

Regressions in include-blob look likely to be just noise.

Tweak `VecCache` to improve performance [#138405](https://github.com/rust-lang/rust/pull/138405) [(Comparison Link)](https://perf.rust-lang.org/compare.html?start=8340622e14324d0090a6edf42fce44fea3d7824f&end=57d2fb136650d05efb3ed3ea33b330bfc85844d5&stat=instructions:u)

| (instructions:u) | mean | range | count |
|:----------------------------------:|:-----:|:--------------:|:-----:|
| Regressions ❌ <br /> (primary) | - | - | 0 |
| Regressions ❌ <br /> (secondary) | 0.1% | [0.0%, 0.2%] | 3 |
| Improvements ✅ <br /> (primary) | -0.4% | [-1.2%, -0.2%] | 126 |
| Improvements ✅ <br /> (secondary) | -0.5% | [-1.3%, -0.0%] | 93 |
| All ❌✅ (primary) | -0.4% | [-1.2%, -0.2%] | 126 |

Regressions in include-blob look likely to be just noise.

Rollup of 5 pull requests [#151816](https://github.com/rust-lang/rust/pull/151816) [(Comparison Link)](https://perf.rust-lang.org/compare.html?start=80b898258da78fdd1262438126aa0cf90e395f0c&end=370143facfb348ad3b29749c0393402d76b280c3&stat=instructions:u)

| (instructions:u) | mean | range | count |
|:----------------------------------:|:-----:|:--------------:|:-----:|
| Regressions ❌ <br /> (primary) | 0.3% | [0.3%, 0.3%] | 2 |
| Regressions ❌ <br /> (secondary) | 0.5% | [0.5%, 0.5%] | 1 |
| Improvements ✅ <br /> (primary) | -0.3% | [-0.7%, -0.2%] | 9 |
| Improvements ✅ <br /> (secondary) | -0.4% | [-0.7%, -0.1%] | 22 |
| All ❌✅ (primary) | -0.2% | [-0.7%, 0.3%] | 11 |

[Doc builds improved, likely due to the portable SIMD subtree update](https://github.com/rust-lang/rust/pull/151775#issuecomment-3821741947)

Regressions are (new) noise in typenum.

#### Mixed

Rollup of 4 pull requests [#151749](https://github.com/rust-lang/rust/pull/151749) [(Comparison Link)](https://perf.rust-lang.org/compare.html?start=94a0cd15f5976fa35e5e6784e621c04e9f958e57&end=e96bb7e44fbcc23c1e6009e8d0ee8ab208668fb4&stat=instructions:u)

| (instructions:u) | mean | range | count |
|:----------------------------------:|:-----:|:--------------:|:-----:|
| Regressions ❌ <br /> (primary) | 0.4% | [0.4%, 0.4%] | 1 |
| Regressions ❌ <br /> (secondary) | 0.1% | [0.0%, 0.1%] | 3 |
| Improvements ✅ <br /> (primary) | -0.2% | [-0.4%, -0.1%] | 22 |
| Improvements ✅ <br /> (secondary) | -0.5% | [-1.9%, -0.1%] | 53 |
| All ❌✅ (primary) | -0.2% | [-0.4%, 0.4%] | 23 |

This is essentially an improvement, the regressions look spurious. The
improvements appear to be due to
[#151711](https://github.com/rust-lang/rust/pull/151711) which updated stdarch.
Why that caused improvements is unclear at this time.

Update to LLVM 22 [#150722](https://github.com/rust-lang/rust/pull/150722) [(Comparison Link)](https://perf.rust-lang.org/compare.html?start=e96bb7e44fbcc23c1e6009e8d0ee8ab208668fb4&end=466ea4e6c39f8a43727edcc726ca86b499e14d83&stat=instructions:u)

| (instructions:u) | mean | range | count |
|:----------------------------------:|:-----:|:---------------:|:-----:|
| Regressions ❌ <br /> (primary) | 3.2% | [0.9%, 7.4%] | 3 |
| Regressions ❌ <br /> (secondary) | 2.3% | [0.4%, 6.0%] | 3 |
| Improvements ✅ <br /> (primary) | -0.7% | [-2.8%, -0.2%] | 238 |
| Improvements ✅ <br /> (secondary) | -0.9% | [-10.1%, -0.1%] | 299 |
| All ❌✅ (primary) | -0.6% | [-2.8%, 7.4%] | 241 |

Lots of affected benchmarks (as normal), but overall a positive LLVM update by
instruction counts. As nnethercote@ notes, the cycle counts are a little red
([comment](https://github.com/rust-lang/rust/pull/150722#issuecomment-3814373587))
as we've seen before with LLVM updates.

Tweak `SlicePartialEq` to allow MIR-inlining the `compare_bytes` call [#150945](https://github.com/rust-lang/rust/pull/150945) [(Comparison Link)](https://perf.rust-lang.org/compare.html?start=a234ae6b6538d41de6886cb7742d062ad832b0e3&end=1e5065a4d99e0e3ccf1a1719055308e7a20e8f36&stat=instructions:u)

| (instructions:u) | mean | range | count |
|:----------------------------------:|:-----:|:--------------:|:-----:|
| Regressions ❌ <br /> (primary) | 0.4% | [0.3%, 0.6%] | 6 |
| Regressions ❌ <br /> (secondary) | 0.7% | [0.7%, 0.7%] | 1 |
| Improvements ✅ <br /> (primary) | -0.9% | [-2.3%, -0.1%] | 7 |
| Improvements ✅ <br /> (secondary) | -2.3% | [-2.3%, -2.3%] | 1 |
| All ❌✅ (primary) | -0.3% | [-2.3%, 0.6%] | 13 |

Expected mixed results from an inlining change. Overall positive.
Loading