[MPS] Speedup argmax/argmin
#159524
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[MPS] Speedup argmax/argmin
#159524
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🔗 Helpful Links🧪 See artifacts and rendered test results at hud.pytorch.org/pr/159524
Note: Links to docs will display an error until the docs builds have been completed. ⏳ No Failures, 72 PendingAs of commit adf1276 with merge base 25343b3 ( UNSTABLE - The following job is marked as unstable, possibly due to flakiness on trunk:
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@pytorchbot merge -f "Lint + MPS are green" |
Merge startedYour change will be merged immediately since you used the force (-f) flag, bypassing any CI checks (ETA: 1-5 minutes). Please use Learn more about merging in the wiki. Questions? Feedback? Please reach out to the PyTorch DevX Team |
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By using efficient `threadgroup_arg[max|min]` primitives.
- Fixed bug in `simd_argmax` when result of the `simd_ballot` were prematurely cast to `ushort` and adjusted unit test
- Fixed nan handling in compiled argmax, but can't reliably test it as MPS(eager) implementaiton of argmax is buggy
Now according to `bench_mps_ops.py` `max(x, dim=0)` is reliably faster than eager implementaiton:
```
[--------------------------------------------------------------------------------------------- --------------------------------------------------------------------------------------------]
| eager-512x512 | compile-512x512 | eager-1024x1024 | compile-1024x1024 | eager-2048x2048 | compile-2048x2048 | eager-4096x4096 | compile-4096x4096
1 threads: ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
max (torch.float16) | 285.8 | 272.2 | 422.3 | 354.5 | 721.6 | 683.5 | 2224.0 | 1979.1
max (torch.float32) | 300.2 | 267.0 | 389.6 | 342.5 | 769.4 | 682.6 | 2995.7 | 2609.8
max (torch.int32) | 299.6 | 275.4 | 390.0 | 361.7 | 758.7 | 686.1 | 3103.4 | 2646.5
max (torch.int64) | 297.5 | 275.5 | 417.0 | 382.1 | 856.1 | 722.6 | 5467.7 | 3156.8
```
Pull Request resolved: #159524
Approved by: https://github.com/Skylion007, https://github.com/dcci
ghstack dependencies: #158990
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Stack from ghstack (oldest at bottom):
argmax/argmin#159524By using efficient
threadgroup_arg[max|min]primitives.simd_argmaxwhen result of thesimd_ballotwere prematurely cast toushortand adjusted unit testNow according to
bench_mps_ops.pymax(x, dim=0)is reliably faster than eager implementaiton:cc @voznesenskym @penguinwu @EikanWang @jgong5 @Guobing-Chen @XiaobingSuper @zhuhaozhe @blzheng @wenzhe-nrv @jiayisunx @ipiszy @chenyang78 @kadeng @muchulee8 @amjames @chauhang @aakhundov @coconutruben