[fsdp] impl save/load shard model/optimizer

[ericxsun]

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resolved https://github.com/hpcaitech/ColossalAI/issues/5328

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[ericxsun]

Could someone in colossalai review it?

Thx. cc @flybird11111

[ver217]

Could you add unit tests to check this feature?

[ericxsun]

Could you add unit tests to check this feature?

I've tested in my local experiments

But how to test it in unittest: colossalai/tests

[ver217]

Could you add unit tests to check this feature?

I've tested in my local experiments

But how to test it in unittest: colossalai/tests

You can add your tests in tests/test_checkpoint_io/test_torch_fsdp_checkpoint_io.py and just run pytest tests/test_checkpoint_io/test_torch_fsdp_checkpoint_io.py. Thanks!

[ericxsun]

Could you add unit tests to check this feature?

I've tested in my local experiments But how to test it in unittest: colossalai/tests

You can add your tests in tests/test_checkpoint_io/test_torch_fsdp_checkpoint_io.py and just run pytest tests/test_checkpoint_io/test_torch_fsdp_checkpoint_io.py. Thanks!

Okay

[ericxsun]

@ver217

pytest tests/test_checkpoint_io/test_torch_fsdp_checkpoint_io.py
================================================================= test session starts ==================================================================
platform linux -- Python 3.10.11, pytest-8.0.0, pluggy-1.4.0
rootdir: ~/ColossalAI
configfile: pytest.ini
plugins: hypothesis-6.75.2, anyio-4.0.0
collected 1 item

tests/test_checkpoint_io/test_torch_fsdp_checkpoint_io.py .                                                                                      [100%]

================================================================== 1 passed in 6.91s ===================================================================