CloudAI Benchmark Framework v1.5.0

NCCL

This workload (test_template_name is NcclTest) allows users to execute NCCL benchmarks within the CloudAI framework.

Test TOML example:

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name = "my_nccl_test" description = "Example NCCL test" test_template_name = "NcclTest" [cmd_args] docker_image_url = "nvcr.io#nvidia/pytorch:25.06-py3"

Test Scenario example:

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name = "nccl-test" [[Tests]] id = "nccl.1" num_nodes = 1 time_limit = "00:05:00" test_name = "my_nccl_test"

Test-in-Scenario example:

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name = "nccl-test" [[Tests]] id = "nccl.1" num_nodes = 1 time_limit = "00:05:00" name = "my_nccl_test" description = "Example NCCL test" test_template_name = "NcclTest" [Tests.cmd_args] docker_image_url = "nvcr.io#nvidia/pytorch:25.06-py3" subtest_name = "all_reduce_perf_mpi" iters = 100

Command Arguments

class cloudai.workloads.nccl_test.nccl.NCCLCmdArgs(*, docker_image_url: str, subtest_name: Literal['all_reduce_perf_mpi', 'all_gather_perf_mpi', 'alltoall_perf_mpi', 'broadcast_perf_mpi', 'gather_perf_mpi', 'hypercube_perf_mpi', 'reduce_perf_mpi', 'reduce_scatter_perf_mpi', 'scatter_perf_mpi', 'sendrecv_perf_mpi', 'bisection_perf_mpi', 'all_reduce_perf', 'all_gather_perf', 'alltoall_perf', 'broadcast_perf', 'gather_perf', 'hypercube_perf', 'reduce_perf', 'reduce_scatter_perf', 'scatter_perf', 'sendrecv_perf', 'bisection_perf'] | list[Literal['all_reduce_perf_mpi', 'all_gather_perf_mpi', 'alltoall_perf_mpi', 'broadcast_perf_mpi', 'gather_perf_mpi', 'hypercube_perf_mpi', 'reduce_perf_mpi', 'reduce_scatter_perf_mpi', 'scatter_perf_mpi', 'sendrecv_perf_mpi', 'bisection_perf_mpi', 'all_reduce_perf', 'all_gather_perf', 'alltoall_perf', 'broadcast_perf', 'gather_perf', 'hypercube_perf', 'reduce_perf', 'reduce_scatter_perf', 'scatter_perf', 'sendrecv_perf', 'bisection_perf']] = 'all_reduce_perf_mpi', nthreads: int | list[int] = 1, ngpus: int | list[int] = 1, minbytes: str | list[str] = '32M', maxbytes: str | list[str] = '32M', stepbytes: str | list[str] = '1M', op: Literal['sum', 'prod', 'min', 'max', 'avg', 'all'] | list[Literal['sum', 'prod', 'min', 'max', 'avg', 'all']] = 'sum', datatype: Literal['uint8', 'float'] | list[Literal['uint8', 'float']] = 'float', root: int | list[int] = 0, iters: int | list[int] = 20, warmup_iters: int | list[int] = 5, agg_iters: int | list[int] = 1, average: int | list[int] = 1, parallel_init: int | list[int] = 0, check: int | list[int] = 1, blocking: int | list[int] = 0, cudagraph: int | list[int] = 0, stepfactor: int | list[int] | None = None, **extra_data: Any)[source]

Bases: CmdArgs

NCCL test command arguments.

docker_image_url: str
subtest_name: Literal['all_reduce_perf_mpi', 'all_gather_perf_mpi', 'alltoall_perf_mpi', 'broadcast_perf_mpi', 'gather_perf_mpi', 'hypercube_perf_mpi', 'reduce_perf_mpi', 'reduce_scatter_perf_mpi', 'scatter_perf_mpi', 'sendrecv_perf_mpi', 'bisection_perf_mpi', 'all_reduce_perf', 'all_gather_perf', 'alltoall_perf', 'broadcast_perf', 'gather_perf', 'hypercube_perf', 'reduce_perf', 'reduce_scatter_perf', 'scatter_perf', 'sendrecv_perf', 'bisection_perf'] | list[Literal['all_reduce_perf_mpi', 'all_gather_perf_mpi', 'alltoall_perf_mpi', 'broadcast_perf_mpi', 'gather_perf_mpi', 'hypercube_perf_mpi', 'reduce_perf_mpi', 'reduce_scatter_perf_mpi', 'scatter_perf_mpi', 'sendrecv_perf_mpi', 'bisection_perf_mpi', 'all_reduce_perf', 'all_gather_perf', 'alltoall_perf', 'broadcast_perf', 'gather_perf', 'hypercube_perf', 'reduce_perf', 'reduce_scatter_perf', 'scatter_perf', 'sendrecv_perf', 'bisection_perf']]
nthreads: int | list[int]
ngpus: int | list[int]
minbytes: str | list[str]
maxbytes: str | list[str]
stepbytes: str | list[str]
op: Literal['sum', 'prod', 'min', 'max', 'avg', 'all'] | list[Literal['sum', 'prod', 'min', 'max', 'avg', 'all']]
datatype: Literal['uint8', 'float'] | list[Literal['uint8', 'float']]
root: int | list[int]
iters: int | list[int]
warmup_iters: int | list[int]
agg_iters: int | list[int]
average: int | list[int]
parallel_init: int | list[int]
check: int | list[int]
blocking: int | list[int]
cudagraph: int | list[int]
stepfactor: int | list[int] | None

Test Definition

class cloudai.workloads.nccl_test.nccl.NCCLTestDefinition(*, name: str, description: str, test_template_name: str, cmd_args: NCCLCmdArgs, extra_env_vars: dict[str, str | List[str]] = {}, extra_cmd_args: dict[str, str] = {}, extra_container_mounts: list[str] = [], git_repos: list[GitRepo] = [], nsys: NsysConfiguration | None = None, predictor: PredictorConfig | None = None, agent: str = 'grid_search', agent_steps: int = 1, agent_metrics: list[str] = ['default'], agent_reward_function: str = 'inverse')[source]

Bases: TestDefinition

Test object for NCCL.

cmd_args: NCCLCmdArgs
property extra_args_str: str
property docker_image: DockerImage
property installables: list[Installable]
was_run_successful(tr: TestRun) → JobStatusResult[source]
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