Migrate from rmm::cuda_stream_view to cuda::stream_ref by bdice · Pull Request #5014 · NVIDIA/cudf-spark-jni

bdice · 2026-08-17T21:49:01Z

Summary

Migrate all JNI uses of rmm::cuda_stream_view to cuda::stream_ref.
Replace the legacy stream-view header with <cuda/stream> and use stream.get() and stream.sync() with the new API.

greptile-apps · 2026-08-17T21:52:18Z

Greptile Summary

The PR migrates native CUDA stream handling from rmm::cuda_stream_view to cuda::stream_ref across GPU primitives, tests, and benchmarks.

Updates native interfaces and raw CUDA calls to use cuda::stream_ref, stream.get(), and stream.sync().
Advances the cuDF submodule and native dependency pins to support the migrated API.
Preserves the existing JNI-facing operation and result contracts.

Confidence Score: 5/5

The PR appears safe to merge because no blocking failure remains in the reviewed follow-up scope.

No blocking failure remains.

Important Files Changed

Filename	Overview
src/main/cpp/src/bloom_filter.cu	Migrates stream parameters, raw CUDA operations, kernel launches, and explicit synchronization to the new stream API without changing Bloom filter behavior.
src/main/cpp/src/protobuf/protobuf_kernels.cu	Updates Protobuf CUDA kernel plumbing to accept and propagate `cuda::stream_ref`.
src/main/cpp/src/row_conversion.cu	Migrates row-conversion stream propagation and raw stream access while retaining existing data-conversion logic.
src/main/cpp/src/shuffle_split.cu	Updates shuffle stream interfaces and CUDA operation submission to the new stream representation.
src/main/cpp/src/cast_string.hpp	Changes public native helper declarations and defaults from the legacy RMM stream view to `cuda::stream_ref`.
thirdparty/cudf-pins/versions.json	Updates pinned native dependencies alongside the cuDF revision used by the stream API migration.
thirdparty/cudf	Advances the cuDF submodule revision supporting the migrated native stream interfaces.

Flowchart

%%{init: {'theme': 'neutral'}}%%
flowchart LR
  A[JNI and native callers] --> B[cuda::stream_ref]
  B --> C[cuDF and RMM operations]
  B --> D[Raw CUDA APIs via stream.get]
  B --> E[Host synchronization via stream.sync]
  F[cuDF submodule and dependency pins] --> C
  F --> D

_{Reviews (7): Last reviewed commit: "Merge remote-tracking branch 'origin/mai..." | Re-trigger Greptile}

Signed-off-by: Bradley Dice <bdice@bradleydice.com>

mythrocks · 2026-08-17T22:16:59Z

Build

mythrocks · 2026-08-17T22:28:15Z

For the record, the immediate problem of the build-error in hll++ was already addressed by @vyasr as part of #5003. That explains why I didn't run into this failure when testing #5012. (I thought I might've missed something when merging #5003 on Friday.)

All that said, switching to the new cuda::stream_ref is still valuable.

Resolve the stream_ref conflicts to match d4f603d9027baa31556a2522baa6ca2e0231d5a0, including thirdparty/cudf at 5316f3696226.

Signed-off-by: MithunR <mithunr@nvidia.com>

mythrocks · 2026-08-26T23:55:34Z

Build

mythrocks · 2026-08-26T23:55:51Z

I have resolved conflicts, and updated to latest.

mythrocks · 2026-08-27T00:03:07Z

Now that I've laid a hand on it, I'm not sure if I can approve this PR. 🤦

thirtiseven · 2026-08-27T03:17:49Z

pre-commit.ci autofix

pmattione-nvidia · 2026-08-27T20:55:23Z

      "always_download" : true,
      "git_shallow" : false,
-      "git_tag" : "9af39e27161d680083b8c309b9040f8c944d68ad",
+      "git_tag" : "26bd4831585ce34294bce6bb3324d648cfd31747",


why is kvikio tag updated?

That should not have been. That's a rogue edit. I'm testing with a corrected version.

Thank you for catching that, @pmattione-nvidia.

igorpeshansky · 2026-08-27T21:07:10Z

Looks like there are still merge conflicts?..

mythrocks · 2026-08-27T21:55:24Z

Looks like there are still merge conflicts?

Yep. It's a little surprising. I'm sorting them out now.

mythrocks · 2026-08-27T22:23:01Z

It appears the CI failure results from NVIDIA/cudf#23803, and is being addressed in NVIDIA/cudf#23862.

I'll update the thirdparty/cudf pointer to exclude NVIDIA/cudf/pull/23803.

1. Moved thirdparty/cudf to exclude NVIDIA/cudf/pull/23803. 2. Corrected kvikio version tag. Signed-off-by: MithunR <mithunr@nvidia.com>

mythrocks · 2026-08-28T01:18:26Z

Build

mythrocks · 2026-08-28T01:21:43Z

Sorry this took so long. thirdparty/cudf kept moving, confusing the merge.

@igorpeshansky / @pmattione-nvidia: Would either of you mind having another look?

igorpeshansky · 2026-08-28T02:51:30Z

 void generate_buckets(GeneratorFunc generator,
                      cudf::mutable_column_view output,
-                      rmm::cuda_stream_view stream)
+                      cuda::stream_ref stream)


[Optional] Do we want to #include <cuda/stream> (IWYU)? Or do we not add one if we pick it up transitively through our own header?

Also in iceberg/iceberg_datetime_util.cu, iceberg/iceberg_truncate.cu, protobuf/protobuf.cu, protobuf/protobuf_builders.cu, protobuf/protobuf_kernels.cu, aggregation64_utils.cu, case_when.cu, cast_string.cu, cast_string_to_float.cu, charset_decode.cu, datetime_rebase.cu, decimal_utils.cu, exception_with_row_index_utilities.cu, get_json_object.cu, histogram.cu, map.cu, map_zip_with_utils.cu, multiply.cu, number_converter.cu, uuid.cu.

igorpeshansky · 2026-08-28T03:21:45Z

This is behind main. I realize you wanted to rewind past NVIDIA/cudf#23803 (per #5014 (comment)), but since the submodule-sync bot advanced it there already, nothing stops it from doing that again, so it won't protect main from breakage. But I guess this is independent of the NVIDIA/cudf#23862 fix, so I won't hold the PR on that.

Ditto for the rmm downgrade in thirdparty/cudf-pins/versions.json…

igorpeshansky · 2026-08-28T04:17:49Z

  int const start,
  int const end,
-  rmm::cuda_stream_view stream      = rmm::cuda_stream_default,
+  cuda::stream_ref stream           = rmm::cuda_stream_default,


Do we also want to switch from rmm::cuda_stream_default to cudf::get_default_stream() here?

Suggested change

cuda::stream_ref stream = rmm::cuda_stream_default,

cuda::stream_ref stream = cudf::get_default_stream(),

Yeah, I can fix this too.

vyasr · 2026-08-28T18:14:42Z

JFYI I'm working on migrating cudf::get_default_stream to cuda::stream_ref as well in NVIDIA/cudf#23770. I won't merge anything there that breaks Spark until this PR is solidified though since it looks like we can get this PR green without that one and then just do one final migration after.

vyasr · 2026-08-28T20:15:47Z

My agent opened #5053 as part of getting NVIDIA/cudf#23770 working, feel free to grab any changes you need from there or just switch to that PR if you would like.

bdice changed the title ~~Replace RMM CUDA stream views with stream refs~~ Migrate from rmm::cuda_stream_view to cuda::stream_ref Aug 17, 2026

bdice force-pushed the cuda-stream-ref branch from 08407ae to 892f38e Compare August 17, 2026 21:49

sameerz requested a review from a team August 17, 2026 21:51

bdice force-pushed the cuda-stream-ref branch from 892f38e to 0009af8 Compare August 17, 2026 22:01

Migrate from rmm::cuda_stream_view to cuda::stream_ref

507e331

Signed-off-by: Bradley Dice <bdice@bradleydice.com>

bdice force-pushed the cuda-stream-ref branch from 0009af8 to 507e331 Compare August 17, 2026 22:03

vyasr approved these changes Aug 17, 2026

View reviewed changes

ttnghia previously approved these changes Aug 18, 2026

View reviewed changes

thirtiseven reviewed Aug 18, 2026

View reviewed changes

Comment thread src/main/cpp/src/bloom_filter.cu Outdated

Merge origin/main into cuda stream ref branch

72a5021

Resolve the stream_ref conflicts to match d4f603d9027baa31556a2522baa6ca2e0231d5a0, including thirdparty/cudf at 5316f3696226.

mythrocks dismissed ttnghia’s stale review via 72a5021 August 26, 2026 23:47

Formatting.

62aa0a0

Signed-off-by: MithunR <mithunr@nvidia.com>

pmattione-nvidia reviewed Aug 27, 2026

View reviewed changes

mythrocks self-assigned this Aug 27, 2026

mythrocks mentioned this pull request Aug 27, 2026

Fix CUDA 13 LTO architecture selection with older CMake NVIDIA/cudf#23862

Open

3 tasks

Merge remote-tracking branch 'origin/main' into bdice-cuda-stream-ref

1c42f54

mythrocks added 2 commits August 27, 2026 16:02

Review changes:

8bf6b6d

1. Moved thirdparty/cudf to exclude NVIDIA/cudf/pull/23803. 2. Corrected kvikio version tag. Signed-off-by: MithunR <mithunr@nvidia.com>

Merge remote-tracking branch 'origin/main' into bdice-cuda-stream-ref

3563025

pmattione-nvidia approved these changes Aug 28, 2026

View reviewed changes

igorpeshansky approved these changes Aug 28, 2026

View reviewed changes

sameerz mentioned this pull request Aug 28, 2026

Rename RAPIDS Accelerator for Apache Spark to NVIDIA cuDF plugin for Apache Spark #5024

Open

This was referenced Aug 28, 2026

Migrate native streams to cuda::stream_ref #5053

Closed

Use cuda::stream_ref for central stream helpers NVIDIA/cudf#23770

Open

	cuda::stream_ref stream = rmm::cuda_stream_default,
	cuda::stream_ref stream = cudf::get_default_stream(),

Uh oh!

Conversation

bdice commented Aug 17, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Summary

Uh oh!

greptile-apps Bot commented Aug 17, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Greptile Summary

Confidence Score: 5/5

Important Files Changed

Flowchart

Uh oh!

mythrocks commented Aug 17, 2026

Uh oh!

mythrocks commented Aug 17, 2026

Uh oh!

Uh oh!

mythrocks commented Aug 26, 2026

Uh oh!

mythrocks commented Aug 26, 2026

Uh oh!

mythrocks commented Aug 27, 2026

Uh oh!

thirtiseven commented Aug 27, 2026

Uh oh!

pmattione-nvidia Aug 27, 2026

Choose a reason for hiding this comment

Uh oh!

mythrocks Aug 27, 2026

Choose a reason for hiding this comment

Uh oh!

mythrocks Aug 27, 2026

Choose a reason for hiding this comment

Uh oh!

igorpeshansky commented Aug 27, 2026

Uh oh!

mythrocks commented Aug 27, 2026

Uh oh!

mythrocks commented Aug 27, 2026

Uh oh!

mythrocks commented Aug 28, 2026

Uh oh!

mythrocks commented Aug 28, 2026

Uh oh!

igorpeshansky Aug 28, 2026

Choose a reason for hiding this comment

Uh oh!

igorpeshansky Aug 28, 2026

Choose a reason for hiding this comment

Uh oh!

igorpeshansky Aug 28, 2026

Choose a reason for hiding this comment

Uh oh!

mythrocks Aug 28, 2026

Choose a reason for hiding this comment

Uh oh!

vyasr commented Aug 28, 2026

Uh oh!

vyasr commented Aug 28, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

8 participants

bdice commented Aug 17, 2026 •

edited

Loading

greptile-apps Bot commented Aug 17, 2026 •

edited

Loading

vyasr commented Aug 28, 2026 •

edited

Loading