Skip to content

Fix SM resource alignment discovery test - #2389

Open
rwgk wants to merge 2 commits into
NVIDIA:mainfrom
rwgk:nvbug6464867_test_green_context_fix
Open

Fix SM resource alignment discovery test#2389
rwgk wants to merge 2 commits into
NVIDIA:mainfrom
rwgk:nvbug6464867_test_green_context_fix

Conversation

@rwgk

@rwgkrwgk commented Jul 19, 2026

Copy link
Copy Markdown
Contributor

Description

Fix the SM resource discovery alignment test for CUDA 13.4 (currently still in developer preview) reported under nvbug 6464867.

Analysis (gpt-5.6-sol)

SMResourceOptions(count=None) produces an unconstrained structured split request. CUDA 13.4 may satisfy that request with every available SM; on B100, that is 148. The device independently reports its default co-scheduling alignment as 8, but that alignment is not imposed unless the request supplies a co-scheduling constraint. The previous 148 % 8 == 0 assertion therefore tested a guarantee the API no longer makes.

Both values come directly from driver-populated resource structures, and cuda.bindings forwards the CUDA 13.4 structured split ABI without calculating either value. This is a cuda.core test expectation issue.

Fix

Explicitly request coscheduled_sm_count=sm_resource.coscheduled_alignment before asserting that the discovered group count is divisible by that alignment. Skip the test when the CUDA driver or bindings predate structured split support (CUDA 13.1), or when the device reports no co-scheduling alignment.

@rwgkrwgk added this to the cuda.core 1.2.0 milestone Jul 19, 2026
@rwgkrwgk self-assigned this Jul 19, 2026
@rwgkrwgk added P0 High priority - Must do! test Improvements or additions to tests cuda.core Everything related to the cuda.core module labels Jul 19, 2026
@copy-pr-bot

Copy link
Copy Markdown
Contributor

Auto-sync is disabled for draft pull requests in this repository. Workflows must be run manually.

Contributors can view more details about this message here.

@rwgk

rwgk commented Jul 19, 2026

Copy link
Copy Markdown
ContributorAuthor

/ok to test 3e7f0fb

@rwgkrwgk added the PR review get-together Mark PRs you'd like the team to review at the weekly PR review get-together. label Jul 19, 2026
@github-actions

Copy link
Copy Markdown

@rwgk
rwgk marked this pull request as ready for review July 19, 2026 18:38
@rwgk
rwgk requested a review from leofangJuly 19, 2026 18:38
# Conflicts:
#	cuda_core/tests/test_green_context.py
Sign up for freeto join this conversation on GitHub. Already have an account? Sign in to comment

Labels

cuda.coreEverything related to the cuda.core moduleP0High priority - Must do!PR review get-togetherMark PRs you'd like the team to review at the weekly PR review get-together.testImprovements or additions to tests

Projects

None yet

Development

Successfully merging this pull request may close these issues.

1 participant

@rwgk