Less aggressive persistent reduction when it could induce large masking with dynamic shapes#163365
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eellison wants to merge 6 commits intogh/eellison/826/basefrom
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Less aggressive persistent reduction when it could induce large masking with dynamic shapes#163365eellison wants to merge 6 commits intogh/eellison/826/basefrom
eellison wants to merge 6 commits intogh/eellison/826/basefrom
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🔗 Helpful Links🧪 See artifacts and rendered test results at hud.pytorch.org/pr/163365
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shunting314
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jansel
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v0i0
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Merge failedReason: This PR has internal changes and must be landed via Phabricator! Please try reimporting/rexporting the PR! Details for Dev Infra teamRaised by workflow job |
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Merge startedYour change will be merged once all checks pass (ETA 0-4 Hours). Learn more about merging in the wiki. Questions? Feedback? Please reach out to the PyTorch DevX Team |
dsashidh
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…ng with dynamic shapes (pytorch#163365) As per comment in source code: ``` # If we are are coalescing on xblock (not ReductionHint.INNER) and this is not a tiny kernel # (not ReductionHint.OUTER_TINY), do not use persistent reduction if it induces tile # quantization. Peristent reduction forces rblock == rnumel, if the bounds between lower # and upper are large, for the lower values we will be masking off large % of read/writes, # when we could expand the coalescing xblock instead. ``` For the test case in question, this pr improves perf from 0.8573521325143717 -> 0.043151492193814305 because we were egregiously masking out rblock values (58/64 values). Differential Revision: [D82853279](https://our.internmc.facebook.com/intern/diff/D82853279) Pull Request resolved: pytorch#163365 Approved by: https://github.com/shunting314, https://github.com/PaulZhang12, https://github.com/jansel, https://github.com/v0i0
jainapurva
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…ng with dynamic shapes (#163365) As per comment in source code: ``` # If we are are coalescing on xblock (not ReductionHint.INNER) and this is not a tiny kernel # (not ReductionHint.OUTER_TINY), do not use persistent reduction if it induces tile # quantization. Peristent reduction forces rblock == rnumel, if the bounds between lower # and upper are large, for the lower values we will be masking off large % of read/writes, # when we could expand the coalescing xblock instead. ``` For the test case in question, this pr improves perf from 0.8573521325143717 -> 0.043151492193814305 because we were egregiously masking out rblock values (58/64 values). Differential Revision: [D82853279](https://our.internmc.facebook.com/intern/diff/D82853279) Pull Request resolved: #163365 Approved by: https://github.com/shunting314, https://github.com/PaulZhang12, https://github.com/jansel, https://github.com/v0i0
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Stack from ghstack (oldest at bottom):
As per comment in source code:
For the test case in question, this pr improves perf from 0.8573521325143717 -> 0.043151492193814305 because we were egregiously masking out rblock values (58/64 values).
cc @voznesenskym @penguinwu @EikanWang @jgong5 @Guobing-Chen @XiaobingSuper @zhuhaozhe @blzheng @wenzhe-nrv @jiayisunx @ipiszy @chenyang78 @kadeng @muchulee8 @amjames @chauhang @aakhundov @coconutruben
Differential Revision: D82853279