pytorch/test/cpp
Howard Huang 9165d46b89 DDP + C10D sparse all_reduce changes (#103916) (#104256)
Summary:

reland of https://github.com/pytorch/pytorch/pull/103916

## Changes

prototyping sparse allreduce using the sparse dispatch key. When passing in sparse tensors into `dist.allreduce()` we can execute our dispatched function.

prior to this change, passing a sparse tensor into `allreduce()` will error out with `Tensor must be dense...`

## Example script

```python
# python -m torch.distributed.run --nnodes=1 --nproc_per_node=2 this_script.py

import torch
import torch.distributed as dist

def main():
    dist.init_process_group(backend="nccl")
    rank = dist.get_rank()
    a = torch.tensor([[0, 2.], [3, 0]]).to(rank)
    a = a.to_sparse()
    print(f"rank {rank} - a: {a}")
    dist.all_reduce(a)

if __name__ == "__main__":
    main()
```

output:
```
rank 1 - a: tensor(indices=tensor([[0, 1],
                       [1, 0]]),
       values=tensor([2., 3.]),
       device='cuda:1', size=(2, 2), nnz=2, layout=torch.sparse_coo)
allreduce_sparse_cuda_
tensor.is_sparse() = 1
in ProcessGroupNCCL::allreduceSparse
rank 0 - a: tensor(indices=tensor([[0, 1],
                       [1, 0]]),
       values=tensor([2., 3.]),
       device='cuda:0', size=(2, 2), nnz=2, layout=torch.sparse_coo)
allreduce_sparse_cuda_
tensor.is_sparse() = 1
in ProcessGroupNCCL::allreduceSparse
```

Test Plan:
Testing commands (OSS):

```
# python
pytest test/distributed/test_c10d_nccl.py -vsk test_sparse_allreduce_ops

# c++
build/bin/ProcessGroupNCCLTest --gtest_filter=ProcessGroupNCCLTest.testSparseAllreduce
```

Testing commands (internal, ondemand GPU):
ddp tests:
```
buck build mode/opt -c hpc_comms.use_ncclexp=default //caffe2/test/distributed:c10d --show-full-output

# Get the .par file from the previous command and use it below
TORCH_SHOW_CPP_STACKTRACE=1 /data/sandcastle/boxes/fbsource/buck-out/v2/gen/fbcode/c8344b52091f4f7f/caffe2/test/distributed/__c10d__/c10d.par -r test_ddp_set_sparse_metadata
```

c10d tests:
```
# build tests and run with log output (python)
buck build mode/opt -c hpc_comms.use_ncclexp=default //caffe2/test/distributed:c10d --show-full-output
NCCL_DEBUG=WARN /data/sandcastle/boxes/fbsource/buck-out/v2/gen/fbcode/c8344b52091f4f7f/caffe2/test/distributed/__c10d__/c10d.par -r test_sparse_allreduce_ops

# python
NCCL_DEBUG=WARN buck test mode/opt -c hpc_comms.use_ncclexp=default //caffe2/test/distributed:c10d -- --exact 'caffe2/test/distributed:c10d - test_sparse_allreduce_ops (test_c10d_nccl.ProcessGroupNCCLTest)'

# c++
NCCL_DEBUG=WARN buck run mode/opt -c hpc_comms.use_ncclexp=default //caffe2/test/cpp/c10d:ProcessGroupNCCLTest -- --gtest_filter=ProcessGroupNCCLTest.testSparseAllreduce
```

Differential Revision: D47056695

Pulled By: H-Huang

Pull Request resolved: https://github.com/pytorch/pytorch/pull/104256
Approved by: https://github.com/rohan-varma
2023-06-28 00:37:52 +00:00
..
aot_inductor Adds the initial support for AOTInductor model and interface (#104202) 2023-06-27 00:37:26 +00:00
api [BE] Enforce missing override keyword (#104032) 2023-06-24 02:34:24 +00:00
c10d DDP + C10D sparse all_reduce changes (#103916) (#104256) 2023-06-28 00:37:52 +00:00
common
dist_autograd
jit [BE] Enforce missing override keyword (#104032) 2023-06-24 02:34:24 +00:00
lazy
lite_interpreter_runtime
monitor
profiler
rpc
tensorexpr Revert "Added round_with_scale_factor arg to ATen (#97868)" 2023-04-28 20:47:00 +00:00
__init__.py