[Data] Don't downscale actors if the operator hasn't received any inputs#59883
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bveeramani merged 5 commits intomasterfrom Jan 6, 2026
Merged
[Data] Don't downscale actors if the operator hasn't received any inputs#59883bveeramani merged 5 commits intomasterfrom
bveeramani merged 5 commits intomasterfrom
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Signed-off-by: Balaji Veeramani <bveeramani@berkeley.edu>
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This pull request prevents the actor autoscaler from downscaling actors if the operator has not yet received any inputs. This is a good fix to prevent premature downscaling, especially in pipelines where an upstream operator might be slow to produce its first output. The implementation is straightforward and a corresponding test case has been added. I've found a minor issue in a test comment that should be corrected for clarity.
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Signed-off-by: Balaji Veeramani <bveeramani@berkeley.edu>
Signed-off-by: Balaji Veeramani <bveeramani@berkeley.edu>
Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com> Signed-off-by: You-Cheng Lin <106612301+owenowenisme@users.noreply.github.com>
…oject/ray into no-downscale-if-no-inputs Signed-off-by: Balaji Veeramani <bveeramani@berkeley.edu>
AYou0207
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…uts (ray-project#59883) If you have a pipeline like `read --> [some cpu transformation] --> [gpu transformation init_concurrency =N] --> write`, the `gpu transformation` might downscale to 0 actors if the CPU transformation is slow. This basically nullifies `init_concurrency` and can cause cold-start delays. --------- Signed-off-by: Balaji Veeramani <bveeramani@berkeley.edu> Signed-off-by: You-Cheng Lin <106612301+owenowenisme@users.noreply.github.com> Co-authored-by: You-Cheng Lin <106612301+owenowenisme@users.noreply.github.com> Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com> Signed-off-by: jasonwrwang <jasonwrwang@tencent.com>
lee1258561
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Feb 3, 2026
…uts (ray-project#59883) If you have a pipeline like `read --> [some cpu transformation] --> [gpu transformation init_concurrency =N] --> write`, the `gpu transformation` might downscale to 0 actors if the CPU transformation is slow. This basically nullifies `init_concurrency` and can cause cold-start delays. --------- Signed-off-by: Balaji Veeramani <bveeramani@berkeley.edu> Signed-off-by: You-Cheng Lin <106612301+owenowenisme@users.noreply.github.com> Co-authored-by: You-Cheng Lin <106612301+owenowenisme@users.noreply.github.com> Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>
ryanaoleary
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Feb 3, 2026
…uts (ray-project#59883) If you have a pipeline like `read --> [some cpu transformation] --> [gpu transformation init_concurrency =N] --> write`, the `gpu transformation` might downscale to 0 actors if the CPU transformation is slow. This basically nullifies `init_concurrency` and can cause cold-start delays. --------- Signed-off-by: Balaji Veeramani <bveeramani@berkeley.edu> Signed-off-by: You-Cheng Lin <106612301+owenowenisme@users.noreply.github.com> Co-authored-by: You-Cheng Lin <106612301+owenowenisme@users.noreply.github.com> Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>
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If you have a pipeline like
read --> [some cpu transformation] --> [gpu transformation init_concurrency =N] --> write, thegpu transformationmight downscale to 0 actors if the CPU transformation is slow. This basically nullifiesinit_concurrencyand can cause cold-start delays.