Use `horde`'s `SyncTable` for default query caches and `CtxtInterners` by Zoxc · Pull Request #153826 · rust-lang/rust

Zoxc · 2026-03-13T15:06:51Z

This uses the hash map from my horde crate as the default query cache map and in CtxtInterners. The main benefit of it is that it offers lock-free reads.

This is a proper version of the test in #138419.

This adds a intermediary SyncTable type which uses our dynamic Lock instead of the always-on lock integrated in horde::SyncTable, as this avoids lock overhead for the -Zthreads=1 case.

This integrates the quiescent state based memory reclamation scheme by marking query execution as quiescent with collect and calling release when we're blocking.

Zoxc · 2026-03-14T11:41:56Z

@bors try @rust-timer queue

Use `horde`'s `SyncTable` for default query caches and `CtxtInterners`

rust-bors · 2026-03-14T13:59:20Z

☀️ Try build successful (CI)
Build commit: 810b08b (810b08be87ff4ade9ca65bf4374cb14ff0468a37, parent: 620e36a8d1fc2f9e5694ce83c2631877651a962c)

rust-timer · 2026-03-14T14:59:21Z

Finished benchmarking commit (810b08b): comparison URL.

Overall result: ❌✅ regressions and improvements - please read the text below

Benchmarking this pull request means it may be perf-sensitive – we'll automatically label it not fit for rolling up. You can override this, but we strongly advise not to, due to possible changes in compiler perf.

Next Steps: If you can justify the regressions found in this try perf run, please do so in sufficient writing along with @rustbot label: +perf-regression-triaged. If not, please fix the regressions and do another perf run. If its results are neutral or positive, the label will be automatically removed.

@bors rollup=never
@rustbot label: -S-waiting-on-perf +perf-regression

Instruction count

Our most reliable metric. Used to determine the overall result above. However, even this metric can be noisy.

	mean	range	count
Regressions ❌ (primary)	0.4%	[0.1%, 1.0%]	123
Regressions ❌ (secondary)	0.7%	[0.1%, 1.9%]	129
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-0.3%	[-0.9%, -0.1%]	12
All ❌✅ (primary)	0.4%	[0.1%, 1.0%]	123

Max RSS (memory usage)

Results (secondary -9.0%)

A less reliable metric. May be of interest, but not used to determine the overall result above.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	1.3%	[0.8%, 2.0%]	4
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-11.6%	[-15.2%, -1.0%]	16
All ❌✅ (primary)	-	-	0

Cycles

Results (primary 3.5%, secondary 3.5%)

A less reliable metric. May be of interest, but not used to determine the overall result above.

	mean	range	count
Regressions ❌ (primary)	3.5%	[1.4%, 7.0%]	54
Regressions ❌ (secondary)	5.0%	[1.9%, 8.9%]	60
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-5.1%	[-7.3%, -2.7%]	11
All ❌✅ (primary)	3.5%	[1.4%, 7.0%]	54

Binary size

This benchmark run did not return any relevant results for this metric.

Bootstrap: 483.729s -> 488.9s (1.07%)
Artifact size: 396.86 MiB -> 395.01 MiB (-0.47%)

Zoxc · 2026-03-15T10:00:50Z

@bors try @rust-timer queue

Use `horde`'s `SyncTable` for default query caches and `CtxtInterners`

rust-bors · 2026-03-15T12:11:29Z

☀️ Try build successful (CI)
Build commit: a20b8ea (a20b8ea6796c024e8171574fe9e57407f66541d1, parent: e0a8361373c88bd791b5b1335c6cbf83cd68e4d5)

rust-timer · 2026-03-15T12:52:20Z

Finished benchmarking commit (a20b8ea): comparison URL.

Overall result: ❌✅ regressions and improvements - please read the text below

Benchmarking this pull request means it may be perf-sensitive – we'll automatically label it not fit for rolling up. You can override this, but we strongly advise not to, due to possible changes in compiler perf.

Next Steps: If you can justify the regressions found in this try perf run, please do so in sufficient writing along with @rustbot label: +perf-regression-triaged. If not, please fix the regressions and do another perf run. If its results are neutral or positive, the label will be automatically removed.

@bors rollup=never
@rustbot label: -S-waiting-on-perf +perf-regression

Instruction count

Our most reliable metric. Used to determine the overall result above. However, even this metric can be noisy.

	mean	range	count
Regressions ❌ (primary)	0.3%	[0.1%, 0.7%]	86
Regressions ❌ (secondary)	0.6%	[0.0%, 1.5%]	107
Improvements ✅ (primary)	-0.2%	[-0.3%, -0.1%]	5
Improvements ✅ (secondary)	-0.3%	[-0.9%, -0.0%]	28
All ❌✅ (primary)	0.3%	[-0.3%, 0.7%]	91

Max RSS (memory usage)

Results (primary 2.6%, secondary -9.3%)

A less reliable metric. May be of interest, but not used to determine the overall result above.

	mean	range	count
Regressions ❌ (primary)	2.6%	[2.6%, 2.6%]	1
Regressions ❌ (secondary)	0.8%	[0.7%, 1.0%]	3
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-11.0%	[-15.3%, -1.0%]	18
All ❌✅ (primary)	2.6%	[2.6%, 2.6%]	1

Cycles

Results (primary 3.4%, secondary 3.0%)

A less reliable metric. May be of interest, but not used to determine the overall result above.

	mean	range	count
Regressions ❌ (primary)	3.4%	[2.2%, 6.5%]	36
Regressions ❌ (secondary)	4.7%	[1.6%, 7.3%]	51
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-4.5%	[-7.1%, -2.0%]	12
All ❌✅ (primary)	3.4%	[2.2%, 6.5%]	36

Binary size

This benchmark run did not return any relevant results for this metric.

Bootstrap: 480.839s -> 488.485s (1.59%)
Artifact size: 396.90 MiB -> 397.07 MiB (0.05%)

Zoxc · 2026-03-15T15:50:28Z

@bors try @rust-timer queue

Use `horde`'s `SyncTable` for default query caches and `CtxtInterners`

rust-bors · 2026-03-15T18:00:10Z

☀️ Try build successful (CI)
Build commit: fbe8224 (fbe822436088fa395ebd12435db3f96d3456d1b2, parent: 9e973d8850334be3fa3bcfb8ed2887d21485e92c)

rust-bors · 2026-03-15T23:06:28Z

☀️ Try build successful (CI)
Build commit: 3ecda27 (3ecda27879be15e793711696512e5874623c0681, parent: d27207d3d64a1399f90344d6ef3c5743204b3fd3)

rust-timer · 2026-03-15T23:46:54Z

Finished benchmarking commit (3ecda27): comparison URL.

Overall result: ❌✅ regressions and improvements - please read the text below

Benchmarking this pull request means it may be perf-sensitive – we'll automatically label it not fit for rolling up. You can override this, but we strongly advise not to, due to possible changes in compiler perf.

Next Steps: If you can justify the regressions found in this try perf run, please do so in sufficient writing along with @rustbot label: +perf-regression-triaged. If not, please fix the regressions and do another perf run. If its results are neutral or positive, the label will be automatically removed.

@bors rollup=never
@rustbot label: -S-waiting-on-perf +perf-regression

Instruction count

Our most reliable metric. Used to determine the overall result above. However, even this metric can be noisy.

	mean	range	count
Regressions ❌ (primary)	0.3%	[0.1%, 0.8%]	84
Regressions ❌ (secondary)	0.6%	[0.0%, 1.9%]	108
Improvements ✅ (primary)	-0.2%	[-0.3%, -0.1%]	6
Improvements ✅ (secondary)	-0.3%	[-1.0%, -0.1%]	30
All ❌✅ (primary)	0.3%	[-0.3%, 0.8%]	90

Max RSS (memory usage)

Results (secondary -10.7%)

A less reliable metric. May be of interest, but not used to determine the overall result above.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	0.9%	[0.9%, 0.9%]	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-11.4%	[-15.1%, -3.8%]	17
All ❌✅ (primary)	-	-	0

Cycles

Results (primary 3.2%, secondary 2.6%)

A less reliable metric. May be of interest, but not used to determine the overall result above.

	mean	range	count
Regressions ❌ (primary)	3.2%	[1.4%, 5.5%]	37
Regressions ❌ (secondary)	4.6%	[1.9%, 7.9%]	47
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-4.6%	[-7.9%, -2.3%]	13
All ❌✅ (primary)	3.2%	[1.4%, 5.5%]	37

Binary size

This benchmark run did not return any relevant results for this metric.

Bootstrap: 481.726s -> 488.008s (1.30%)
Artifact size: 394.80 MiB -> 397.03 MiB (0.56%)

Zoxc · 2026-03-16T09:12:36Z

@bors try @rust-timer queue

Use `horde`'s `SyncTable` for default query caches and `CtxtInterners`

rust-bors · 2026-03-16T11:24:22Z

☀️ Try build successful (CI)
Build commit: 8107a7d (8107a7d016fb925dfd99c26c0011c2c4a9039f30, parent: 5b61449ed85a670f1dd3fca6a8c759ee0b451b66)

rust-timer · 2026-03-16T13:15:54Z

Finished benchmarking commit (8107a7d): comparison URL.

Overall result: ❌✅ regressions and improvements - please read the text below

Benchmarking this pull request means it may be perf-sensitive – we'll automatically label it not fit for rolling up. You can override this, but we strongly advise not to, due to possible changes in compiler perf.

Next Steps: If you can justify the regressions found in this try perf run, please do so in sufficient writing along with @rustbot label: +perf-regression-triaged. If not, please fix the regressions and do another perf run. If its results are neutral or positive, the label will be automatically removed.

@bors rollup=never
@rustbot label: -S-waiting-on-perf +perf-regression

Instruction count

Our most reliable metric. Used to determine the overall result above. However, even this metric can be noisy.

	mean	range	count
Regressions ❌ (primary)	0.4%	[0.2%, 0.7%]	6
Regressions ❌ (secondary)	0.4%	[0.0%, 0.9%]	18
Improvements ✅ (primary)	-0.3%	[-0.8%, -0.1%]	55
Improvements ✅ (secondary)	-0.4%	[-0.8%, -0.1%]	82
All ❌✅ (primary)	-0.2%	[-0.8%, 0.7%]	61

Max RSS (memory usage)

Results (primary 0.5%, secondary -10.6%)

A less reliable metric. May be of interest, but not used to determine the overall result above.

	mean	range	count
Regressions ❌ (primary)	0.5%	[0.5%, 0.5%]	1
Regressions ❌ (secondary)	1.1%	[1.1%, 1.1%]	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-11.3%	[-14.6%, -2.4%]	16
All ❌✅ (primary)	0.5%	[0.5%, 0.5%]	1

Cycles

Results (primary 3.6%, secondary 2.2%)

A less reliable metric. May be of interest, but not used to determine the overall result above.

	mean	range	count
Regressions ❌ (primary)	3.6%	[2.2%, 6.4%]	14
Regressions ❌ (secondary)	4.6%	[2.0%, 6.7%]	22
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-3.8%	[-5.0%, -2.2%]	9
All ❌✅ (primary)	3.6%	[2.2%, 6.4%]	14

Binary size

This benchmark run did not return any relevant results for this metric.

Bootstrap: 481.08s -> 485.518s (0.92%)
Artifact size: 396.88 MiB -> 395.54 MiB (-0.34%)

Zoxc · 2026-03-19T21:33:59Z

Results for 7 threads:

Benchmark	Before	After		Before	After		Before	After
Benchmark	Time	Time	%	Physical Memory	Physical Memory	%	Committed Memory	Committed Memory	%
🟣 clap:check	0.3754s	0.3661s	💚 -2.47%	204.75 MiB	161.39 MiB	💚 -21.18%	274.62 MiB	212.75 MiB	💚 -22.53%
🟣 hyper:check	0.1290s	0.1168s	💚 -9.47%	127.63 MiB	86.49 MiB	💚 -32.23%	195.84 MiB	130.02 MiB	💚 -33.61%
🟣 regex:check	0.2774s	0.2648s	💚 -4.55%	167.31 MiB	121.57 MiB	💚 -27.34%	228.01 MiB	162.14 MiB	💚 -28.89%
🟣 syn:check	0.5331s	0.5166s	💚 -3.09%	198.50 MiB	152.16 MiB	💚 -23.34%	260.45 MiB	195.06 MiB	💚 -25.10%
Total	1.3149s	1.2643s	💚 -3.84%	698.19 MiB	521.61 MiB	💚 -25.29%	958.93 MiB	699.98 MiB	💚 -27.00%
Summary	1.0000s	0.9511s	💚 -4.89%	1 byte	0.74 bytes	💚 -26.02%	1 byte	0.72 bytes	💚 -27.53%

Zoxc · 2026-03-19T21:50:21Z

We should probably do a crater run / ensure this has time to bake in nightly to get some test coverage on horde.

rustbot · 2026-03-19T21:50:30Z

The list of allowed third-party dependencies may have been modified! You must ensure that any new dependencies have compatible licenses before merging.

cc @davidtwco, @wesleywiser

rustbot · 2026-03-19T21:50:32Z

r? @JohnTitor

rustbot has assigned @JohnTitor.
They will have a look at your PR within the next two weeks and either review your PR or reassign to another reviewer.

Use r? to explicitly pick a reviewer

Why was this reviewer chosen?

The reviewer was selected based on:

Owners of files modified in this PR: compiler
compiler expanded to 69 candidates
Random selection from 14 candidates

JohnTitor · 2026-03-19T22:25:20Z

@rustbot reroll