Commit Graph
7 Commits
Author SHA1 Message Date
Chandler CarruthandChristopher Di Bella 361c832713 Add a prelude compilation benchmark (#7368)
Adds `toolchain/benchmarking/prelude_benchmark.cpp`, which measures the
time to compile the Core prelude and reports the most interesting SemIR
memory statistics as benchmark counters.

The prelude is compiled by checking a file that imports it: the implicit
prelude import causes the check phase to lex, parse, and check the full
set of prelude files, so this is a direct measure of prelude compilation
cost. Four input variations exercise increasing amounts of the prelude:
an empty file, a minimal single-type use, an operator-heavy file that
hits many impls, and a compact file that pulls in a wide swath of the
prelude.

Memory usage is queried directly: `Driver::set_mem_usage` takes a
`MemUsage` that a compile merges each file's usage into; the benchmark
passes one, compiles, and sums the entries by label. A compilation unit
collects into its own `MemUsage` whenever usage is dumped or a sink is
provided (decided in `SetMultiUnitCache`); after a file is done it dumps
that `MemUsage` per-file as before and, if a sink was provided, merges
into it via a new `MemUsage::Add(const MemUsage&)` overload. `MemUsage`
also exposes its entries via a public `Entry` type and an `entries()`
accessor.

Also extends `scripts/bench_runner.py` to (1) treat Mem-prefixed
counters as cost metrics (smaller is better) and (2) tolerate metrics
that aren't reported by every benchmark in a binary.

Assisted-by: Claude Code

---------

Co-authored-by: Christopher Di Bella <cjdb.ns@gmail.com>
2026-06-29 05:39:44 +00:00
Dana Jansens 233a58fcb1 Fix ty errors for missing generic parameters (#7326)
Mostly these errors were around `dict` missing arguments, and they are
almost always `[str, Any]`.

But a real thorn here was `xml.etree.ElementTree.Element`. `ty` insists
that this is a generic type, and indeed it appears to be one, or
becoming one, in some python version. But it is not generic in python
3.12. So we are stuck in an unsolvable land where:
- `ty` gives an error unless you write `[str]` on the type, because it
thinks it is generic.
- python3.12 gives an error if you do write `[str]` on the type, because
it thinks it is not generic.

Forcing `ty` to target exactly python 3.12 does not help. So I have just
used a linter-ignore comment on that line.
2026-06-09 15:08:39 +00:00
Chandler Carruth b344f3af12 Switch a few stragglers to uv and update python to 3.12 (#7296)
Not sure how these got missed when moving other things to `uv`, but this
should clean them up.

The bump to Python 3.12 is so that we can use `@override` with the
simple import from `typing`. This is needed by the newest versions of
`ty` to do type checking. Added the relevant `@override` annotations.

Assisted-by: Antigravity with Gemini
2026-06-03 05:34:44 +00:00
Chandler Carruth 3ef128ac91 Switch to Astral Python tools: ruff and ty (#7243)
This replaces black, flake8, and mypy with the more modern and efficient
tools `ruff` and `ty` from Astral.

Assisted-by: Antigravity with Gemini
2026-05-29 22:56:27 +00:00
Jon Ross-Perkins 4b076291c9 pre-commit autoupdate (#6845)
Assisted-by: Google Antigravity with Gemini
2026-03-09 15:49:11 +00:00
Chandler Carruth 1a97021875 Enhance benchmark runner args and defaults (#5797)
There are some very useful default arguments, so teach the runner script
to directly provide them. They can be easily overridden if needed. As
part of this, change the default run count to 10 which much more often
produces statistically significant error bars and results.

Also, tweak the processing of the results to provide a stable order
based on the source order, even when randomized interleaving is enabled.
The randomized interleaving improves the statistical strength of the
benchmarks significantly, but displaying the results in the source order
is much more understandable. This should give roughly the best of both
worlds.
2025-07-11 16:54:51 +00:00
Chandler CarruthandDana Jansens 9a4a9a9730 Introduce a benchmark running script (#5706)
This script runs benchmarks written using Google Benchmark repeatedly,
and collects the results from JSON to render them nicely and provide
statistical information across the runs.

Because this runs the binaries repeatedly, this can help account for
run-to-run variations that are pervasive in many of Carbon's benchmarks,
such as ASLR and other process-specific differences.

It's most basic mode runs a benchmark multiple times and shows both
median and confidence intervals.

It also supports two comparison modes:

1) Regular expressions can be provided that describe collections of
   related benchmarks where one is the "main" benchmark and the others
   are comparable. For example, Carbon's data structure vs. data
   structures from LLVM or Abseil. These will be rendered with the main
   benchmark first, followed by a comparison relative to a "baseline" of
   each comparable benchmark.

2) A baseline benchmark binary, and potentially different command line
   flags, can be provided to run two benchmark binaries and compute
   a comparison for each benchmark within them.

Across all of these, the script works to present the best text UI it can
in the console. I may have gotten a bit obsessed with rendering the
benchmark results in a way that is really pretty. There are lots of
fancy color coding and progress bars, etc., when run in in the terminal.

For the basic mode without any comparisons, the results look like:

```
Computing statistically significant deltas only wherethe P-value < 𝛂 of 0.05
Metric key:
   BenchmarkName...  <median> ± <% at 95th conf>

 Benchmark                                             ┃        CPU Time         ┃    bytes_per_second
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━╇━━━━━━━━━━━━━━━━━━━━━━━━━╇━━━━━━━━━━━━━━━━━━━━━━━━
 BM_LatencyHash<RandValues<uint8_t>, CarbonHashBench>. │    3.051 ns ±   2.721%  │  327.8   M ±   2.765%
 BM_LatencyHash<RandValues<uint8_t>, AbseilHashBench>. │    3.395 ns ±   4.377%  │  294.6   M ±   4.572%
 BM_LatencyHash<RandValues<uint8_t>, LLVMHashBench>... │    6.125 ns ±   2.662%  │  163.3   M ±   2.726%
 BM_LatencyHash<RandValues<uint16_t>, CarbonHashBench> │    3.105 ns ±   3.947%  │  644.1   M ±   4.109%
 BM_LatencyHash<RandValues<uint16_t>, AbseilHashBench> │    3.433 ns ±   4.308%  │  582.6   M ±   4.502%
 BM_LatencyHash<RandValues<uint16_t>, LLVMHashBench>.. │    6.127 ns ±   2.540%  │  326.5   M ±   2.587%
 BM_LatencyHash<RandValues<uint32_t>, CarbonHashBench> │    3.082 ns ±   2.846%  │    1.298 G ±   2.923%
 BM_LatencyHash<RandValues<uint32_t>, AbseilHashBench> │    3.401 ns ±   3.611%  │    1.176 G ±   3.739%
 BM_LatencyHash<RandValues<uint32_t>, LLVMHashBench>.. │    6.209 ns ±   4.064%  │  644.3   M ±   4.236%
 BM_LatencyHash<RandValues<uint64_t>, CarbonHashBench> │    3.122 ns ±   2.871%  │    2.563 G ±   2.956%
 BM_LatencyHash<RandValues<uint64_t>, AbseilHashBench> │    3.426 ns ±   2.811%  │    2.335 G ±   2.892%
 BM_LatencyHash<RandValues<uint64_t>, LLVMHashBench>.. │    6.497 ns ±   3.081%  │    1.231 G ±   3.179%
```

For the first comparison mode on one of Carbon's benchmarks, the results
look like:

```
Computing statistically significant deltas only wherethe P-value < 𝛂 of 0.05
Metric key:
   BenchmarkName...    <median> ± <% at 95th conf>
     vs Comparable: 👍 <delta>    p=<U-test P-value>
                       <median> ± <% at 95th conf>

 Benchmark                                             ┃          CPU Time          ┃     bytes_per_second
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━╇━━━━━━━━━━━━━━━━━━━━━━━━━━━━╇━━━━━━━━━━━━━━━━━━━━━━━━━━━
 BM_LatencyHash<RandValues<uint8_t>, CarbonHashBench>. │      3.037 ns ±   1.781%   │    329.2   M ±   1.813%
                                            vs Abseil: │ 👍  -8.200%     p=0.000183 │ 👍   8.933%    p=0.000183
                                                       │      3.309 ns ±   2.064%   │    302.2   M ±   2.022%
                                              vs LLVM: │ 👍 -49.401%     p=0.000183 │ 👍  97.632%    p=0.000183
                                                       │      6.003 ns ±   1.502%   │    166.6   M ±   1.480%
                                                       │                            │
 BM_LatencyHash<RandValues<uint16_t>, CarbonHashBench> │      3.026 ns ±   1.816%   │    661     M ±   1.784%
                                            vs Abseil: │ 👍  -8.599%     p=0.000183 │ 👍   9.408%    p=0.000183
                                                       │      3.311 ns ±   1.873%   │    604.1   M ±   1.839%
                                              vs LLVM: │ 👍 -49.829%     p=0.000183 │ 👍  99.319%    p=0.000183
                                                       │      6.031 ns ±   2.806%   │    331.6   M ±   2.730%
                                                       │                            │
 BM_LatencyHash<RandValues<uint32_t>, CarbonHashBench> │      3.017 ns ±   2.696%   │      1.326 G ±   2.625%
                                            vs Abseil: │ 👍  -9.754%     p=0.000183 │ 👍  10.808%    p=0.000183
                                                       │      3.344 ns ±   1.537%   │      1.196 G ±   1.514%
                                              vs LLVM: │ 👍 -49.857%     p=0.000183 │ 👍  99.427%    p=0.000183
                                                       │      6.018 ns ±   3.269%   │    664.7   M ±   3.167%
                                                       │                            │
 BM_LatencyHash<RandValues<uint64_t>, CarbonHashBench> │      3.025 ns ±   3.395%   │      2.644 G ±   3.284%
                                            vs Abseil: │ 👍  -9.812%     p=0.000183 │ 👍  10.879%    p=0.000183
                                                       │      3.354 ns ±   2.640%   │      2.385 G ±   2.572%
                                              vs LLVM: │ 👍   0.476x     p=0.000183 │ 👍   2.101x    p=0.000183
                                                       │      6.357 ns ±   2.477%   │      1.258 G ±   2.418%
                                                       │                            │
```

For the second mode, in this case comparing a baseline build with `-Oz`
vs an experiment with `-Os`, the results look like:

```
Computing statistically significant deltas only wherethe P-value < 𝛂 of 0.05
Metric key:
   BenchmarkName... 👍 <delta>    p=<U-test P-value>
          baseline:    <median> ± <% at 95th conf>
        experiment:    <median> ± <% at 95th conf>

 Benchmark                                                                  ┃          CPU Time          ┃     bytes_per_second
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━╇━━━━━━━━━━━━━━━━━━━━━━━━━━━━╇━━━━━━━━━━━━━━━━━━━━━━━━━━━
 BM_LatencyHash<RandValues<std::pair<uint32_t, uint32_t>>, CarbonHashBench> │ 👍 -35.870%     p=0.000557 │ 👍  55.930%    p=0.000557
                                                                  baseline: │      5.704 ns ±   1.877%   │      1.403 G ±   1.911%
                                                                experiment: │      3.658 ns ±   4.209%   │      2.187 G ±   4.039%
                                                                            │                            │
 BM_LatencyHash<RandValues<std::pair<uint32_t, uint64_t>>, CarbonHashBench> │ 👍 -19.475%     p=0.00119  │ 👍  24.186%    p=0.00119
                                                                  baseline: │      4.974 ns ±   3.029%   │      3.217 G ±   3.124%
                                                                experiment: │      4.005 ns ±   4.297%   │      3.995 G ±   4.120%
                                                                            │                            │
 BM_LatencyHash<RandValues<std::pair<uint32_t, int*>>, CarbonHashBench>.... │ 👍 -11.740%     p=0.00153  │ 👍  13.302%    p=0.00153
                                                                  baseline: │      4.634 ns ±   3.433%   │      3.453 G ±   3.555%
                                                                experiment: │      4.09  ns ±   2.999%   │      3.912 G ±   2.911%
                                                                            │                            │
```

The script itself uses a new tool for managing dependencies called `uv`:
https://docs.astral.sh/uv/ This tool allows for the script to contain an
inline set of dependencies that will be installed and cached for
subsequent runs. This seemed particularly important as dependencies like
SciPy and NumPy can be particularly difficult to manager or keep
installed in other ways, but are essential to this scripts statistical
analysis. So far, the `uv` system has been working remarkably well for
me and been a relatively pleasant experience on the whole.

I have included as much of the Python dependencies as have good type
information into the MyPy configuration to get good type checking in
pre-commit however.

Last but not least, this has been a pet project of mine for a quite a
while and so may be a bit rough around the edges as I added and tweaked
functionality based on specific benchmarks I was looking at. It feels
like its gotten useful enough to contribute somewhere, but totally open
to any refactoring or improvements needed. I tried to take a few passes
over it to organize and document the code before sending it, but I'm
sure there are still some things that could use improvement.

---------

Co-authored-by: Dana Jansens <danakj@orodu.net>
2025-06-24 12:47:32 +00:00