Use `ThinVec` for PredicateObligation storage #131422

GnomedDev · 2024-10-09T00:31:47Z

I noticed while profiling clippy on a project that a large amount of time is being spent allocating Vecs for PredicateObligation, and the Vecs are often quite small. This is an attempt to optimise this by using SmallVec to avoid heap allocations for these common small Vecs.

This PR turns all the Vec<PredicateObligation> into a single type alias while avoiding referring to Vec around it, then swaps the type over to ThinVec<PredicateObligation> and fixes the fallout. This also contains an implementation of ThinVec::extract_if, copied from Vec::extract_if and currently being upstreamed to Gankra/thin-vec#66.

This leads to a small (0.2-0.7%) performance gain in the latest perf run.

jieyouxu · 2024-10-09T21:48:17Z

@bors try @rust-timer queue

…ions, r=<try> WIP: Use `SmallVec` for `PredicateObligation` storage I noticed while profiling clippy on a project that a large amount of time is being spent allocating `Vec`s for `PredicateObligation`, and the `Vec`s are often quite small. This is an attempt to optimise this by using SmallVec to avoid heap allocations for these common small Vecs. First, I am making sure a single type alias is being used whenever referring to a Vec of PredicateObligation, then I can swap this type alias to `SmallVec` and test out different amounts of inline storage until I find a sweet spot. This is WIP, now at the stage of checking if this is a performance win and tuning the inline capacity. r? `@ghost`

bors · 2024-10-09T21:49:28Z

⌛ Trying commit 8df8a1b with merge 56bfc05...

bors · 2024-10-09T23:31:50Z

☀️ Try build successful - checks-actions
Build commit: 56bfc05 (56bfc05b38711e7ea2c7eaad3c3c3b4886aeb443)

rust-timer · 2024-10-10T01:47:10Z

Finished benchmarking commit (56bfc05): comparison URL.

Overall result: ❌ regressions - please read the text below

Benchmarking this pull request likely means that it is perf-sensitive, so we're automatically marking it as not fit for rolling up. While you can manually mark this PR as fit for rollup, we strongly recommend not doing so since this PR may lead to changes in compiler perf.

Next Steps: If you can justify the regressions found in this try perf run, please indicate this with @rustbot label: +perf-regression-triaged along with sufficient written justification. If you cannot justify the regressions please fix the regressions and do another perf run. If the next run shows neutral or positive results, the label will be automatically removed.

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

Instruction count

This is the most reliable metric that we have; it was used to determine the overall result at the top of this comment. However, even this metric can sometimes exhibit noise.

	mean	range	count
Regressions ❌ (primary)	2.7%	[0.2%, 8.2%]	163
Regressions ❌ (secondary)	3.5%	[0.2%, 11.5%]	156
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	2.7%	[0.2%, 8.2%]	163

Max RSS (memory usage)

Results (primary -2.2%, secondary 0.7%)

This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	2.7%	[1.5%, 4.2%]	5
Improvements ✅ (primary)	-2.2%	[-4.1%, -1.2%]	3
Improvements ✅ (secondary)	-2.6%	[-2.8%, -2.2%]	3
All ❌✅ (primary)	-2.2%	[-4.1%, -1.2%]	3

Cycles

Results (primary 3.3%, secondary 4.1%)

This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	3.3%	[1.1%, 6.5%]	88
Regressions ❌ (secondary)	4.1%	[2.0%, 11.1%]	83
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	3.3%	[1.1%, 6.5%]	88

Binary size

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

Bootstrap: 776.8s -> 781.301s (0.58%)
Artifact size: 329.51 MiB -> 329.82 MiB (0.10%)

jieyouxu · 2024-10-10T07:49:57Z

@bors try @rust-timer queue

…ions, r=<try> WIP: Use `SmallVec` for `PredicateObligation` storage I noticed while profiling clippy on a project that a large amount of time is being spent allocating `Vec`s for `PredicateObligation`, and the `Vec`s are often quite small. This is an attempt to optimise this by using SmallVec to avoid heap allocations for these common small Vecs. First, I am making sure a single type alias is being used whenever referring to a Vec of PredicateObligation, then I can swap this type alias to `SmallVec` and test out different amounts of inline storage until I find a sweet spot. This is WIP, now at the stage of checking if this is a performance win and tuning the inline capacity. - Heavy (0-11%) performance drop with `4` inline capacity. r? `@ghost`

bors · 2024-10-10T07:51:08Z

⌛ Trying commit fda8da9 with merge 90ae6a8...

bors · 2024-10-10T08:04:21Z

💔 Test failed - checks-actions

fee1-dead · 2024-10-13T15:08:37Z

r? compiler

compiler-errors · 2024-10-13T15:17:56Z

@bors r+ rollup=never

bors · 2024-10-13T15:17:58Z

📌 Commit 8de8f46 has been approved by compiler-errors

It is now in the queue for this repository.

bors · 2024-10-14T15:03:37Z

⌛ Testing commit 8de8f46 with merge 2bc47d2...

…ions, r=compiler-errors Use `ThinVec` for PredicateObligation storage ~~I noticed while profiling clippy on a project that a large amount of time is being spent allocating `Vec`s for `PredicateObligation`, and the `Vec`s are often quite small. This is an attempt to optimise this by using SmallVec to avoid heap allocations for these common small Vecs.~~ This PR turns all the `Vec<PredicateObligation>` into a single type alias while avoiding referring to `Vec` around it, then swaps the type over to `ThinVec<PredicateObligation>` and fixes the fallout. This also contains an implementation of `ThinVec::extract_if`, copied from `Vec::extract_if` and currently being upstreamed to Gankra/thin-vec#66. This leads to a small (0.2-0.7%) performance gain in the latest perf run.

bors · 2024-10-14T15:07:23Z

💔 Test failed - checks-actions

rust-log-analyzer · 2024-10-14T15:08:09Z

A job failed! Check out the build log: (web) (plain)

Click to see the possible cause of the failure (guessed by this bot)

#4 [auth] library/ubuntu:pull token for registry-1.docker.io
#4 DONE 0.0s

#3 [internal] load metadata for docker.io/library/ubuntu:22.04
#3 ERROR: failed to copy: httpReadSeeker: failed open: unexpected status code https://registry-1.docker.io/v2/library/ubuntu/manifests/sha256:58b87898e82351c6cf9cf5b9f3c20257bb9e2dcf33af051e12ce532d7f94e3fe: 429 Too Many Requests - Server message: toomanyrequests: You have reached your pull rate limit. You may increase the limit by authenticating and upgrading: https://www.docker.com/increase-rate-limit
 > [internal] load metadata for docker.io/library/ubuntu:22.04:
------
Dockerfile:1
--------------------
--------------------
   1 | >>> FROM ubuntu:22.04
   2 |     
   3 |     COPY scripts/cross-apt-packages.sh /scripts/
--------------------
ERROR: failed to solve: ubuntu:22.04: failed to resolve source metadata for docker.io/library/ubuntu:22.04: failed to copy: httpReadSeeker: failed open: unexpected status code https://registry-1.docker.io/v2/library/ubuntu/manifests/sha256:58b87898e82351c6cf9cf5b9f3c20257bb9e2dcf33af051e12ce532d7f94e3fe: 429 Too Many Requests - Server message: toomanyrequests: You have reached your pull rate limit. You may increase the limit by authenticating and upgrading: https://www.docker.com/increase-rate-limit
#0 building with "tender_albattani" instance using docker-container driver

#1 [internal] load build definition from Dockerfile
#1 transferring dockerfile: 966B done
#1 transferring dockerfile: 966B done
#1 DONE 0.0s

#2 [internal] load metadata for docker.io/library/ubuntu:22.04
#2 ERROR: failed to copy: httpReadSeeker: failed open: unexpected status code https://registry-1.docker.io/v2/library/ubuntu/manifests/sha256:58b87898e82351c6cf9cf5b9f3c20257bb9e2dcf33af051e12ce532d7f94e3fe: 429 Too Many Requests - Server message: toomanyrequests: You have reached your pull rate limit. You may increase the limit by authenticating and upgrading: https://www.docker.com/increase-rate-limit
 > [internal] load metadata for docker.io/library/ubuntu:22.04:
------
Dockerfile:1
--------------------
--------------------
   1 | >>> FROM ubuntu:22.04
   2 |     
   3 |     COPY scripts/cross-apt-packages.sh /scripts/
--------------------
ERROR: failed to solve: ubuntu:22.04: failed to resolve source metadata for docker.io/library/ubuntu:22.04: failed to copy: httpReadSeeker: failed open: unexpected status code https://registry-1.docker.io/v2/library/ubuntu/manifests/sha256:58b87898e82351c6cf9cf5b9f3c20257bb9e2dcf33af051e12ce532d7f94e3fe: 429 Too Many Requests - Server message: toomanyrequests: You have reached your pull rate limit. You may increase the limit by authenticating and upgrading: https://www.docker.com/increase-rate-limit
#0 building with "tender_albattani" instance using docker-container driver

#1 [internal] load build definition from Dockerfile
#1 transferring dockerfile: 966B done
#1 transferring dockerfile: 966B done
#1 DONE 0.0s

#2 [internal] load metadata for docker.io/library/ubuntu:22.04
#2 ERROR: failed to copy: httpReadSeeker: failed open: unexpected status code https://registry-1.docker.io/v2/library/ubuntu/manifests/sha256:58b87898e82351c6cf9cf5b9f3c20257bb9e2dcf33af051e12ce532d7f94e3fe: 429 Too Many Requests - Server message: toomanyrequests: You have reached your pull rate limit. You may increase the limit by authenticating and upgrading: https://www.docker.com/increase-rate-limit
 > [internal] load metadata for docker.io/library/ubuntu:22.04:
------
Dockerfile:1
--------------------
--------------------
   1 | >>> FROM ubuntu:22.04
   2 |     
   3 |     COPY scripts/cross-apt-packages.sh /scripts/
--------------------
ERROR: failed to solve: ubuntu:22.04: failed to resolve source metadata for docker.io/library/ubuntu:22.04: failed to copy: httpReadSeeker: failed open: unexpected status code https://registry-1.docker.io/v2/library/ubuntu/manifests/sha256:58b87898e82351c6cf9cf5b9f3c20257bb9e2dcf33af051e12ce532d7f94e3fe: 429 Too Many Requests - Server message: toomanyrequests: You have reached your pull rate limit. You may increase the limit by authenticating and upgrading: https://www.docker.com/increase-rate-limit
#0 building with "tender_albattani" instance using docker-container driver

#1 [internal] load build definition from Dockerfile
#1 transferring dockerfile: 966B done
#1 transferring dockerfile: 966B done
#1 DONE 0.0s

#2 [internal] load metadata for docker.io/library/ubuntu:22.04
#2 ERROR: failed to copy: httpReadSeeker: failed open: unexpected status code https://registry-1.docker.io/v2/library/ubuntu/manifests/sha256:58b87898e82351c6cf9cf5b9f3c20257bb9e2dcf33af051e12ce532d7f94e3fe: 429 Too Many Requests - Server message: toomanyrequests: You have reached your pull rate limit. You may increase the limit by authenticating and upgrading: https://www.docker.com/increase-rate-limit
 > [internal] load metadata for docker.io/library/ubuntu:22.04:
------
Dockerfile:1
--------------------
--------------------
   1 | >>> FROM ubuntu:22.04
   2 |     
   3 |     COPY scripts/cross-apt-packages.sh /scripts/
--------------------
ERROR: failed to solve: ubuntu:22.04: failed to resolve source metadata for docker.io/library/ubuntu:22.04: failed to copy: httpReadSeeker: failed open: unexpected status code https://registry-1.docker.io/v2/library/ubuntu/manifests/sha256:58b87898e82351c6cf9cf5b9f3c20257bb9e2dcf33af051e12ce532d7f94e3fe: 429 Too Many Requests - Server message: toomanyrequests: You have reached your pull rate limit. You may increase the limit by authenticating and upgrading: https://www.docker.com/increase-rate-limit
#0 building with "tender_albattani" instance using docker-container driver

#1 [internal] load build definition from Dockerfile
#1 transferring dockerfile: 966B done
#1 transferring dockerfile: 966B done
#1 DONE 0.0s

#2 [internal] load metadata for docker.io/library/ubuntu:22.04
#2 ERROR: failed to copy: httpReadSeeker: failed open: unexpected status code https://registry-1.docker.io/v2/library/ubuntu/manifests/sha256:58b87898e82351c6cf9cf5b9f3c20257bb9e2dcf33af051e12ce532d7f94e3fe: 429 Too Many Requests - Server message: toomanyrequests: You have reached your pull rate limit. You may increase the limit by authenticating and upgrading: https://www.docker.com/increase-rate-limit
 > [internal] load metadata for docker.io/library/ubuntu:22.04:
------
Dockerfile:1
--------------------
--------------------
   1 | >>> FROM ubuntu:22.04
   2 |     
   3 |     COPY scripts/cross-apt-packages.sh /scripts/
--------------------
ERROR: failed to solve: ubuntu:22.04: failed to resolve source metadata for docker.io/library/ubuntu:22.04: failed to copy: httpReadSeeker: failed open: unexpected status code https://registry-1.docker.io/v2/library/ubuntu/manifests/sha256:58b87898e82351c6cf9cf5b9f3c20257bb9e2dcf33af051e12ce532d7f94e3fe: 429 Too Many Requests - Server message: toomanyrequests: You have reached your pull rate limit. You may increase the limit by authenticating and upgrading: https://www.docker.com/increase-rate-limit
##[error]Process completed with exit code 1.
Post job cleanup.

matthiaskrgr · 2024-10-14T15:11:53Z

@bors retry

bors · 2024-10-16T04:06:17Z

⌛ Testing commit 8de8f46 with merge 9618da7...

bors · 2024-10-16T06:34:27Z

☀️ Test successful - checks-actions
Approved by: compiler-errors
Pushing 9618da7 to master...

rust-timer · 2024-10-16T07:52:00Z

Finished benchmarking commit (9618da7): comparison URL.

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

Our benchmarks found a performance regression caused by this PR.
This might be an actual regression, but it can also be just noise.

Next Steps:

If the regression was expected or you think it can be justified,
please write a comment with sufficient written justification, and add
@rustbot label: +perf-regression-triaged to it, to mark the regression as triaged.
If you think that you know of a way to resolve the regression, try to create
a new PR with a fix for the regression.
If you do not understand the regression or you think that it is just noise,
you can ask the @rust-lang/wg-compiler-performance working group for help (members of this group
were already notified of this PR).

@rustbot label: +perf-regression
cc @rust-lang/wg-compiler-performance

Instruction count

This is the most reliable metric that we have; it was used to determine the overall result at the top of this comment. However, even this metric can sometimes exhibit noise.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	0.3%	[0.3%, 0.5%]	8
Improvements ✅ (primary)	-0.3%	[-0.7%, -0.2%]	15
Improvements ✅ (secondary)	-0.3%	[-0.7%, -0.2%]	23
All ❌✅ (primary)	-0.3%	[-0.7%, -0.2%]	15

Max RSS (memory usage)

Results (primary -1.0%, secondary -0.5%)

This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	1.2%	[1.2%, 1.2%]	1
Regressions ❌ (secondary)	3.4%	[3.4%, 3.4%]	2
Improvements ✅ (primary)	-2.1%	[-2.6%, -1.6%]	2
Improvements ✅ (secondary)	-3.2%	[-5.2%, -2.0%]	3
All ❌✅ (primary)	-1.0%	[-2.6%, 1.2%]	3

Cycles

Results (secondary 1.7%)

This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	1.7%	[1.7%, 1.7%]	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-	-	0

Binary size

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

Bootstrap: 782.214s -> 781.789s (-0.05%)
Artifact size: 333.77 MiB -> 333.88 MiB (0.03%)

Kobzol · 2024-10-16T09:02:15Z

Nice results! :) Good find.

rustbot added S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. T-compiler Relevant to the compiler team, which will review and decide on the PR/issue. WG-trait-system-refactor The Rustc Trait System Refactor Initiative labels Oct 9, 2024