Files
xc-llm-ascend/vllm_ascend
Frank Chen a77fe932e4 [Platform] Fix CPU binding logic (#6889)
### What this PR does / why we need it?

- Rework CpuAlloc.handle_no_affinity() to build available NUMA nodes
after allowed_cpus filtering, assign NPUs to NUMA nodes via round‑robin,
and split CPUs per NPU with disjoint slices for better balance.
- Improve bind_memory() robustness by deriving the target NUMA from each
NPU’s CPU pool, validating NUMA existence, and skipping binding when
data is missing.
- bind_memory() now only bind the single NUMA node that corresponds to
NPU id, instead of 2 NUMA nodes.
- Fix the issue that all NPUs bind to 0th NUMA node when DP16 due to
global NPU id is not visible across DP domain.

### Does this PR introduce _any_ user-facing change?

No.

### How was this patch tested?

Added/updated unit tests:

test_cpu_binding.py
1.   test_binding_mode_table covers A2 vs A3 binding mode mapping.
2. test_build_cpu_pools_fallback_to_numa_balanced covers fallback when
affinity info is missing.
3. TestBindingSwitch.test_is_arm_cpu covers ARM/x86/unknown arch
detection.
4.   test_bind_cpus_skip_non_arm covers non‑ARM skip path in bind_cpus.

test_worker_v1.py
1. Updated mocks for enable_cpu_binding default True to align with new
config default.

- vLLM version: v0.16.0
- vLLM main:
15d76f74e2

Signed-off-by: chenchuw886 <chenchuw@huawei.com>
Co-authored-by: chenchuw886 <chenchuw@huawei.com>
2026-03-01 20:30:43 +08:00
..
2026-02-28 09:20:57 +08:00
2026-02-28 09:20:57 +08:00
2026-02-28 09:20:57 +08:00