Optimize union type creation by ahejlsberg · Pull Request #53771 · microsoft/TypeScript

ahejlsberg · 2023-04-14T01:42:12Z

This PR implements two optimizations to our union type creation logic:

When resolving the type Record<A, B>[A], where A and B are large union types, we end up creating a union type from a list of types B, B, ..., B, where B is repeated as many times as the size of A. The union type creation logic collects the constituent type list by "flattening" each B, which ends up generating a lot of useless work. We now detect that we've already processed B and ignore all but the first occurrence.
We now cache the results of unioning a pair of types, where one or both are union types, by a key constructed from the two type identities. Previously, we'd first flatten all of the (non-union) types into a combined set, which is a lot more work for large unions. This in particular helps for repeated creations of U | undefined where U is some large union type.

The check time for the example in #53761 effectively drops to zero with these optimizations.

ahejlsberg · 2023-04-14T01:43:20Z

@typescript-bot test this
@typescript-bot user test this inline
@typescript-bot run dt
@typescript-bot perf test faster
@typescript-bot test top100

typescript-bot · 2023-04-14T01:43:23Z

Heya @ahejlsberg, I've started to run the parallelized Definitely Typed test suite on this PR at 46d1c4e. You can monitor the build here.

Update: The results are in!

typescript-bot · 2023-04-14T01:43:23Z

Heya @ahejlsberg, I've started to run the extended test suite on this PR at 46d1c4e. You can monitor the build here.

typescript-bot · 2023-04-14T01:43:23Z

Heya @ahejlsberg, I've started to run the diff-based user code test suite on this PR at 46d1c4e. You can monitor the build here.

Update: The results are in!

typescript-bot · 2023-04-14T01:43:24Z

Heya @ahejlsberg, I've started to run the diff-based top-repos suite on this PR at 46d1c4e. You can monitor the build here.

Update: The results are in!

typescript-bot · 2023-04-14T01:43:24Z

Heya @ahejlsberg, I've started to run the abridged perf test suite on this PR at 46d1c4e. You can monitor the build here.

Update: The results are in!

typescript-bot · 2023-04-14T01:54:27Z

@ahejlsberg Here are the results of running the user test suite comparing main and refs/pull/53771/merge:

There were infrastructure failures potentially unrelated to your change:

1 instance of "Package install failed"

Otherwise...

Everything looks good!

typescript-bot · 2023-04-14T01:58:43Z

@ahejlsberg
The results of the perf run you requested are in!

Here they are:

Comparison Report - main..53771

_Metric	_main	₅₃₇₇₁	_Delta	_Best	_Worst	_p-value
_{Angular - node (v16.17.1, x64)}
_{Memory used}	_{364,558k (± 0.01%)}	_{364,581k (± 0.01%)}	_~	_364,534k	_364,605k	_{p=0.199 n=6}
_{Parse Time}	_{3.54s (± 0.49%)}	_{3.56s (± 0.66%)}	_~	_3.53s	_3.59s	_{p=0.371 n=6}
_{Bind Time}	_{1.17s (± 0.47%)}	_{1.18s (± 0.76%)}	_~	_1.17s	_1.19s	_{p=0.341 n=6}
_{Check Time}	_{9.54s (± 0.49%)}	_{9.50s (± 0.39%)}	_~	_9.46s	_9.56s	_{p=0.195 n=6}
_{Emit Time}	_{7.97s (± 0.64%)}	_{7.96s (± 0.44%)}	_~	_7.92s	_8.00s	_{p=0.807 n=6}
_{Total Time}	_{22.22s (± 0.22%)}	_{22.20s (± 0.32%)}	_~	_22.11s	_22.27s	_{p=0.572 n=6}
_{Compiler-Unions - node (v16.17.1, x64)}
_{Memory used}	_{192,423k (± 0.02%)}	_{192,605k (± 0.04%)}	_{+182k (+ 0.09%)}	_192,455k	_192,680k	_{p=0.013 n=6}
_{Parse Time}	_{1.59s (± 0.79%)}	_{1.59s (± 0.65%)}	_~	_1.57s	_1.60s	_{p=0.560 n=6}
_{Bind Time}	_{0.83s (± 0.66%)}	_{0.82s (± 0.63%)}	_~	_0.82s	_0.83s	_{p=0.640 n=6}
_{Check Time}	_{10.36s (± 0.37%)}	_{10.21s (± 0.72%)}	_{-0.15s (- 1.46%)}	_10.15s	_10.30s	_{p=0.005 n=6}
_{Emit Time}	_{3.00s (± 1.48%)}	_{2.98s (± 0.84%)}	_~	_2.96s	_3.02s	_{p=0.627 n=6}
_{Total Time}	_{15.78s (± 0.52%)}	_{15.61s (± 0.48%)}	_{-0.17s (- 1.07%)}	_15.51s	_15.72s	_{p=0.010 n=6}
_{Monaco - node (v16.17.1, x64)}
_{Memory used}	_{345,774k (± 0.00%)}	_{345,784k (± 0.00%)}	_~	_345,771k	_345,809k	_{p=0.261 n=6}
_{Parse Time}	_{2.72s (± 0.31%)}	_{2.72s (± 0.49%)}	_~	_2.70s	_2.74s	_{p=0.280 n=6}
_{Bind Time}	_{1.08s (± 1.23%)}	_{1.08s (± 0.50%)}	_~	_1.08s	_1.09s	_{p=0.663 n=6}
_{Check Time}	_{7.81s (± 0.57%)}	_{7.83s (± 0.53%)}	_~	_7.79s	_7.88s	_{p=0.454 n=6}
_{Emit Time}	_{4.46s (± 1.36%)}	_{4.48s (± 1.03%)}	_~	_4.44s	_4.53s	_{p=0.514 n=6}
_{Total Time}	_{16.07s (± 0.44%)}	_{16.12s (± 0.40%)}	_~	_16.04s	_16.19s	_{p=0.198 n=6}
_{TFS - node (v16.17.1, x64)}
_{Memory used}	_{300,049k (± 0.00%)}	_{300,047k (± 0.01%)}	_~	_300,024k	_300,082k	_{p=0.936 n=6}
_{Parse Time}	_{2.17s (± 0.35%)}	_{2.16s (± 0.51%)}	_~	_2.15s	_2.18s	_{p=0.068 n=6}
_{Bind Time}	_{1.23s (± 0.33%)}	_{1.24s (± 1.22%)}	_~	_1.22s	_1.26s	_{p=0.498 n=6}
_{Check Time}	_{7.22s (± 0.20%)}	_{7.18s (± 0.50%)}	_~	_7.13s	_7.23s	_{p=0.106 n=6}
_{Emit Time}	_{4.35s (± 0.86%)}	_{4.33s (± 0.63%)}	_~	_4.30s	_4.37s	_{p=0.292 n=6}
_{Total Time}	_{14.97s (± 0.21%)}	_{14.91s (± 0.39%)}	_~	_14.84s	_15.00s	_{p=0.107 n=6}
_{material-ui - node (v16.17.1, x64)}
_{Memory used}	_{479,359k (± 0.01%)}	_{481,107k (± 0.00%)}	_{+1,749k (+ 0.36%)}	_481,092k	_481,128k	_{p=0.005 n=6}
_{Parse Time}	_{3.24s (± 0.16%)}	_{3.23s (± 0.47%)}	_~	_3.22s	_3.26s	_{p=0.198 n=6}
_{Bind Time}	_{0.95s (± 0.79%)}	_{0.95s (± 0.54%)}	_~	_0.94s	_0.95s	_{p=0.241 n=6}
_{Check Time}	_{18.00s (± 0.82%)}	_{17.78s (± 0.22%)}	_{-0.21s (- 1.18%)}	_17.71s	_17.82s	_{p=0.005 n=6}
_{Emit Time}	_{0.00s (± 0.00%)}	_{0.00s (± 0.00%)}	_~	_0.00s	_0.00s	_{p=1.000 n=6}
_{Total Time}	_{22.19s (± 0.68%)}	_{21.97s (± 0.20%)}	_{-0.22s (- 1.00%)}	_21.89s	_22.01s	_{p=0.005 n=6}
_{xstate - node (v16.17.1, x64)}
_{Memory used}	_{559,387k (± 0.02%)}	_{559,338k (± 0.01%)}	_~	_559,297k	_559,408k	_{p=0.689 n=6}
_{Parse Time}	_{3.99s (± 0.19%)}	_{3.98s (± 0.49%)}	_~	_3.95s	_4.00s	_{p=0.871 n=6}
_{Bind Time}	_{1.75s (± 0.36%)}	_{1.74s (± 0.43%)}	_~	_1.73s	_1.75s	_{p=0.081 n=6}
_{Check Time}	_{3.06s (± 0.91%)}	_{3.03s (± 0.46%)}	_{-0.04s (- 1.25%)}	_3.00s	_3.04s	_{p=0.004 n=6}
_{Emit Time}	_{0.10s (± 5.34%)}	_{0.09s (± 0.00%)}	_{🟩-0.01s (- 6.90%)}	_0.09s	_0.09s	_{p=0.025 n=6}
_{Total Time}	_{8.90s (± 0.24%)}	_{8.84s (± 0.30%)}	_{-0.06s (- 0.69%)}	_8.81s	_8.88s	_{p=0.006 n=6}

System

_{Machine Name}	_ts-ci-ubuntu
_Platform	_{linux 5.4.0-135-generic}
_Architecture	_x64
_{Available Memory}	_{16 GB}
_{Available Memory}	_{15 GB}
_CPUs	_{4 × Intel(R) Core(TM) i7-4770 CPU @ 3.40GHz}

Hosts

node (v16.17.1, x64)

Scenarios

Angular - node (v16.17.1, x64)
Compiler-Unions - node (v16.17.1, x64)
Monaco - node (v16.17.1, x64)
TFS - node (v16.17.1, x64)
material-ui - node (v16.17.1, x64)
xstate - node (v16.17.1, x64)

_Benchmark	_Name	_Iterations
_Current	₅₃₇₇₁	₆
_Baseline	_main	₆

Developer Information:

Download Benchmark

jakebailey

Very nice!

typescript-bot · 2023-04-14T03:36:05Z

@ahejlsberg Here are the results of running the top-repos suite comparing main and refs/pull/53771/merge:

Everything looks good!

typescript-bot · 2023-04-14T03:47:09Z

Hey @ahejlsberg, the results of running the DT tests are ready.
Everything looks the same!
You can check the log here.

jakebailey · 2023-04-14T15:51:50Z

@typescript-bot perf test this faster

typescript-bot · 2023-04-14T15:51:54Z

Heya @jakebailey, I've started to run the abridged perf test suite on this PR at 14f30d3. You can monitor the build here.

Update: The results are in!

src/compiler/checker.ts

typescript-bot · 2023-04-14T16:07:18Z

@jakebailey
The results of the perf run you requested are in!

Here they are:

Comparison Report - main..53771

_Metric	_main	₅₃₇₇₁	_Delta	_Best	_Worst	_p-value
_{Angular - node (v16.17.1, x64)}
_{Memory used}	_{364,587k (± 0.00%)}	_{364,606k (± 0.01%)}	_~	_364,542k	_364,631k	_{p=0.065 n=6}
_{Parse Time}	_{3.54s (± 0.46%)}	_{3.55s (± 0.49%)}	_~	_3.54s	_3.58s	_{p=0.210 n=6}
_{Bind Time}	_{1.17s (± 1.04%)}	_{1.18s (± 0.76%)}	_~	_1.17s	_1.19s	_{p=0.445 n=6}
_{Check Time}	_{9.52s (± 0.57%)}	_{9.49s (± 0.62%)}	_~	_9.40s	_9.56s	_{p=0.872 n=6}
_{Emit Time}	_{7.96s (± 0.31%)}	_{7.94s (± 0.66%)}	_~	_7.88s	_8.03s	_{p=0.467 n=6}
_{Total Time}	_{22.20s (± 0.27%)}	_{22.17s (± 0.43%)}	_~	_22.06s	_22.27s	_{p=0.689 n=6}
_{Compiler-Unions - node (v16.17.1, x64)}
_{Memory used}	_{192,362k (± 0.01%)}	_{192,536k (± 0.02%)}	_{+174k (+ 0.09%)}	_192,479k	_192,582k	_{p=0.005 n=6}
_{Parse Time}	_{1.59s (± 0.83%)}	_{1.58s (± 0.96%)}	_~	_1.56s	_1.60s	_{p=0.511 n=6}
_{Bind Time}	_{0.82s (± 0.63%)}	_{0.82s (± 0.63%)}	_~	_0.82s	_0.83s	_{p=1.000 n=6}
_{Check Time}	_{10.36s (± 0.48%)}	_{10.27s (± 0.64%)}	_{-0.08s (- 0.79%)}	_10.19s	_10.39s	_{p=0.037 n=6}
_{Emit Time}	_{3.00s (± 0.63%)}	_{3.00s (± 1.02%)}	_~	_2.95s	_3.03s	_{p=1.000 n=6}
_{Total Time}	_{15.77s (± 0.35%)}	_{15.69s (± 0.55%)}	_~	_15.60s	_15.84s	_{p=0.065 n=6}
_{Monaco - node (v16.17.1, x64)}
_{Memory used}	_{345,772k (± 0.00%)}	_{345,785k (± 0.01%)}	_~	_345,763k	_345,808k	_{p=0.230 n=6}
_{Parse Time}	_{2.72s (± 0.49%)}	_{2.72s (± 0.68%)}	_~	_2.71s	_2.76s	_{p=0.732 n=6}
_{Bind Time}	_{1.08s (± 0.48%)}	_{1.08s (± 1.01%)}	_~	_1.06s	_1.09s	_{p=0.784 n=6}
_{Check Time}	_{7.82s (± 0.76%)}	_{7.83s (± 0.41%)}	_~	_7.80s	_7.89s	_{p=0.421 n=6}
_{Emit Time}	_{4.47s (± 0.61%)}	_{4.46s (± 0.36%)}	_~	_4.44s	_4.48s	_{p=0.458 n=6}
_{Total Time}	_{16.10s (± 0.51%)}	_{16.10s (± 0.22%)}	_~	_16.05s	_16.15s	_{p=0.571 n=6}
_{TFS - node (v16.17.1, x64)}
_{Memory used}	_{300,041k (± 0.01%)}	_{300,049k (± 0.01%)}	_~	_300,028k	_300,085k	_{p=0.810 n=6}
_{Parse Time}	_{2.16s (± 0.38%)}	_{2.16s (± 0.35%)}	_~	_2.15s	_2.17s	_{p=0.729 n=6}
_{Bind Time}	_{1.23s (± 1.03%)}	_{1.24s (± 0.85%)}	_~	_1.22s	_1.25s	_{p=0.456 n=6}
_{Check Time}	_{7.22s (± 0.67%)}	_{7.18s (± 0.25%)}	_~	_7.15s	_7.20s	_{p=0.169 n=6}
_{Emit Time}	_{4.32s (± 0.27%)}	_{4.35s (± 1.00%)}	_~	_4.31s	_4.41s	_{p=0.460 n=6}
_{Total Time}	_{14.94s (± 0.31%)}	_{14.93s (± 0.40%)}	_~	_14.85s	_15.00s	_{p=0.686 n=6}
_{material-ui - node (v16.17.1, x64)}
_{Memory used}	_{479,399k (± 0.01%)}	_{481,114k (± 0.00%)}	_{+1,715k (+ 0.36%)}	_481,092k	_481,148k	_{p=0.005 n=6}
_{Parse Time}	_{3.24s (± 0.42%)}	_{3.25s (± 0.36%)}	_~	_3.23s	_3.26s	_{p=0.562 n=6}
_{Bind Time}	_{0.95s (± 0.67%)}	_{0.95s (± 0.79%)}	_~	_0.94s	_0.96s	_{p=0.718 n=6}
_{Check Time}	_{17.97s (± 0.34%)}	_{17.80s (± 0.38%)}	_{-0.17s (- 0.95%)}	_17.73s	_17.90s	_{p=0.008 n=6}
_{Emit Time}	_{0.00s (± 0.00%)}	_{0.00s (± 0.00%)}	_~	_0.00s	_0.00s	_{p=1.000 n=6}
_{Total Time}	_{22.17s (± 0.32%)}	_{22.00s (± 0.32%)}	_{-0.16s (- 0.74%)}	_21.91s	_22.09s	_{p=0.013 n=6}
_{xstate - node (v16.17.1, x64)}
_{Memory used}	_{559,327k (± 0.03%)}	_{559,363k (± 0.02%)}	_~	_559,254k	_559,487k	_{p=0.471 n=6}
_{Parse Time}	_{3.99s (± 0.49%)}	_{3.99s (± 0.20%)}	_~	_3.98s	_4.00s	_{p=1.000 n=6}
_{Bind Time}	_{1.75s (± 0.30%)}	_{1.75s (± 0.00%)}	_~	_1.75s	_1.75s	_{p=0.174 n=6}
_{Check Time}	_{3.06s (± 0.27%)}	_{3.03s (± 0.84%)}	_~	_3.01s	_3.08s	_{p=0.063 n=6}
_{Emit Time}	_{0.10s (± 5.34%)}	_{0.09s (± 0.00%)}	_{🟩-0.01s (- 6.90%)}	_0.09s	_0.09s	_{p=0.025 n=6}
_{Total Time}	_{8.89s (± 0.18%)}	_{8.86s (± 0.31%)}	_{-0.03s (- 0.37%)}	_8.83s	_8.91s	_{p=0.036 n=6}

System

_{Machine Name}	_ts-ci-ubuntu
_Platform	_{linux 5.4.0-135-generic}
_Architecture	_x64
_{Available Memory}	_{16 GB}
_{Available Memory}	_{15 GB}
_CPUs	_{4 × Intel(R) Core(TM) i7-4770 CPU @ 3.40GHz}

Hosts

node (v16.17.1, x64)

Scenarios

Angular - node (v16.17.1, x64)
Compiler-Unions - node (v16.17.1, x64)
Monaco - node (v16.17.1, x64)
TFS - node (v16.17.1, x64)
material-ui - node (v16.17.1, x64)
xstate - node (v16.17.1, x64)

_Benchmark	_Name	_Iterations
_Current	₅₃₇₇₁	₆
_Baseline	_main	₆

Developer Information:

Download Benchmark

jakebailey

Approved x2 😄

ahejlsberg added 2 commits April 13, 2023 17:40

Optimize union type creation

5e29a0a

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46d1c4e

typescript-bot assigned ahejlsberg Apr 14, 2023

typescript-bot added Author: Team For Uncommitted Bug PR for untriaged, rejected, closed or missing bug labels Apr 14, 2023

typescript-bot added For Milestone Bug PRs that fix a bug with a specific milestone and removed For Uncommitted Bug PR for untriaged, rejected, closed or missing bug labels Apr 14, 2023

ahejlsberg requested review from DanielRosenwasser, RyanCavanaugh and jakebailey April 14, 2023 01:45

jakebailey approved these changes Apr 14, 2023

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Sort cache key / cache last type instead of just last union

14f30d3

jakebailey reviewed Apr 14, 2023

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Address CR feedback

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jakebailey approved these changes Apr 14, 2023

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ahejlsberg merged commit b798e6b into main Apr 14, 2023

ahejlsberg deleted the fix53761 branch April 14, 2023 16:34

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