onnxruntime

c85f6eb9 - Add --test_parallel to reduce CTest concurrency for ASan builds (#28675)

Add --test_parallel to reduce CTest concurrency for ASan builds (#28675) ## Description The `windows_x64_asan / build_x64` CI pipeline has been failing with OOM (out-of-memory) because ASan-instrumented test binaries consume significantly more memory than normal builds, and CTest was running them at full CPU-count parallelism. This PR adds a `--test_parallel` argument to `build.py` that allows CTest concurrency to be configured independently from the build parallelism (`--parallel`). It then uses `--test_parallel 4` in the Windows x64 ASan workflow to cap test execution to 4 parallel jobs, preventing OOM while keeping build parallelism at full speed. ## Motivation and Context - ASan instrumentation inflates per-process memory usage by ~2-3x. - The existing `--parallel` flag controls both MSBuild and CTest concurrency together; there was no way to keep fast parallel builds while limiting test concurrency. - The CI runner has limited memory, and running all tests in parallel under ASan exceeded available RAM. ## Changes | File | Change | |------|--------| | `tools/ci_build/build_args.py` | Add `--test_parallel` argument (default: `None`, falls back to `--parallel`) | | `tools/ci_build/build.py` | Add `number_of_test_parallel_jobs()` helper; use it for CTest `--parallel`; validate negative values | | `.github/workflows/windows_build_x64_asan.yml` | Pass `--test_parallel 4` to cap ASan test concurrency | ## Testing - `python -m py_compile tools/ci_build/build.py tools/ci_build/build_args.py` — passes - `python tools/ci_build/build.py --help` shows the new `--test_parallel` option - `git diff --check` — no whitespace issues - When `--test_parallel` is omitted, behavior is unchanged (falls back to `--parallel` value)