[https://nvbugs/6105768][fix] ** Runtime GPU detection inside the test function: when total_memory < 80 GiB

[tensorrt-cicd]

Summary

• Root cause: ** DeepSeek-V3-Lite bf16 model requires ~37 GiB per disaggregated worker. With two workers (context + generation) sharing a single L40S GPU (44.4 GiB), total memory needed is ~74 GiB, causing OOM during model._apply(init_meta_tensor). The test was designed for H100 (80 GiB) with workers on separate GPUs but had no memory guard.
• Fix: ** Runtime GPU detection inside the test function: when total_memory < 80 GiB and device_count < 2, fall back to TinyLlama-1.1B-Chat-v1.0 (~2 GiB) with a dedicated small-model config (disagg_config_cancel_stress_test_small.yaml) that uses conservative free_gpu_memory_fraction values (0.2/0.3 vs 0.3/0.85) to prevent KV cache allocation races on shared GPUs. The parametrize ID [DeepSeek-V3-Lite-bf16] is preserved since it comes from the fixture parameter, not the actual model loaded. On H100 or multi-GPU systems, the original DeepSeek-V3-Lite bf16 path is unchanged.
• Automated fix generated by repair-bot

Test plan

• Verify fix on the same GPU type as the original failure
• Check for regressions in related tests

Links

• Bug: https://nvbugs/6105768

Summary by CodeRabbit

• Tests

  • Added a new small-scale cancellation stress test configuration.
  • Enhanced cancellation test logic to intelligently select model and configuration based on available GPU memory.
  • Improved support for single-GPU systems with lower memory configurations.

• Chores

  • Re-enabled a previously skipped large-context cancellation test.

[coderabbitai]

📝 Walkthrough

Walkthrough

Introduces a new disaggregated cancellation stress test configuration with TinyLlama model. Updates the test runner with a prompt_len_range parameter and GPU-aware fallback logic that selects model and configuration based on available GPU memory. Removes an existing test waiver directive.

Changes

Cohort / File(s)	Summary
Test Configuration tests/integration/defs/disaggregated/test_configs/disagg_config_cancel_stress_test_small.yaml	New YAML configuration file for disaggregated cancellation stress testing with TinyLlama-1.1B model, including tensor/pipeline parallelization, KV cache reuse settings, cache transceiver configuration, and CUDA graph options.
Test Logic tests/integration/defs/disaggregated/test_disaggregated.py	Adds prompt_len_range parameter to run_disaggregated_cancel_test() function and implements conditional logic to detect GPU count and memory, falling back to TinyLlama with reduced prompt range on single-GPU systems with <80 GiB memory.
Waiver Updates tests/integration/test_lists/waives.txt	Removes SKIP waiver for test_disaggregated_cancel_large_context_requests[DeepSeek-V3-Lite-bf16].

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~25 minutes

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title is mostly related to the main change, identifying the runtime GPU detection logic as the key fix, though it is somewhat verbose with extra asterisks and incomplete sentence structure.
Description check	✅ Passed	The PR description provides clear context on root cause, the fix implementation, and testing approach, though it lacks explicit coverage of the PR checklist items from the template.
Docstring Coverage	✅ Passed	Docstring coverage is 100.00% which is sufficient. The required threshold is 80.00%.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

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[coderabbitai]

🧹 Nitpick comments (1)

tests/integration/defs/disaggregated/test_disaggregated.py (1)

1-1: Consider updating copyright year.

The copyright header shows 2022-2024, but since this file is being modified in 2026, it should be updated to 2022-2026 per coding guidelines. As per coding guidelines: "update year on modified files".

📝 Proposed fix

-# SPDX-FileCopyrightText: Copyright (c) 2022-2024 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+# SPDX-FileCopyrightText: Copyright (c) 2022-2026 NVIDIA CORPORATION & AFFILIATES. All rights reserved.

🤖 Prompt for AI Agents

Verify each finding against the current code and only fix it if needed.

In `@tests/integration/defs/disaggregated/test_disaggregated.py` at line 1, Update
the copyright header year range in test_disaggregated.py from "2022-2024" to
"2022-2026" so the file reflects the current modification year; locate the
SPDX/header comment at the top of the file and change the year substring
accordingly.

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.

Nitpick comments:
In `@tests/integration/defs/disaggregated/test_disaggregated.py`:
- Line 1: Update the copyright header year range in test_disaggregated.py from
"2022-2024" to "2022-2026" so the file reflects the current modification year;
locate the SPDX/header comment at the top of the file and change the year
substring accordingly.

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Path: .coderabbit.yaml

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Plan: Enterprise

Run ID: 5baeccdf-3fcb-478d-926d-8942b9c81d28

📥 Commits

Reviewing files that changed from the base of the PR and between eeba2eb and ba07791.

📒 Files selected for processing (3)

• tests/integration/defs/disaggregated/test_configs/disagg_config_cancel_stress_test_small.yaml
• tests/integration/defs/disaggregated/test_disaggregated.py
• tests/integration/test_lists/waives.txt

💤 Files with no reviewable changes (1)

• tests/integration/test_lists/waives.txt