Lightning

**Full Changelog**: https://github.com/Lightning-AI/lightning/compare/1.9.0...2.0.0rc0

App

Changed

- Added `healthz` endpoint to plugin server (16882)
- System customization syncing for jobs run (16932)

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Fabric

Changed

- Let `TorchCollective` works on the `torch.distributed` WORLD process group by default (16995)

Fixed

- fixed for all `_cuda_clearCublasWorkspaces` on teardown (16907)
- Improved the error message for installing tensorboard or tensorboardx (17053)

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PyTorch

Changed

- Changed to the `NeptuneLogger` (16761):
* It now supports neptune-client 0.16.16 and neptune >=1.0, and we have replaced the `log()` method with `append()` and `extend()`.
* It now accepts a namespace `Handler` as an alternative to `Run` for the `run` argument. This means that you can call it like `NeptuneLogger(run=run["some/namespace"])` to log everything to the `some/namespace/` location of the run.
- Allow `sys.argv` and args in `LightningCLI` (16808)
- Moveed HPU broadcast override to the HPU strategy file (17011)

Depercated

- Removed registration of `ShardedTensor` state dict hooks in `LightningModule.__init__` with `torch>=2.1` (16892)
- Removed the `lightning.pytorch.core.saving.ModelIO` class interface (16974)

Fixed

- Fixed `num_nodes` not being set for `DDPFullyShardedNativeStrategy` (17160)
- Fixed parsing the precision config for inference in `DeepSpeedStrategy` (16973)
- Fixed the availability check for `rich` that prevented Lightning to be imported in Google Colab (17156)
- Fixed for all `_cuda_clearCublasWorkspaces` on teardown (16907)
- The `psutil` package is now required for CPU monitoring (17010)
- Improved the error message for installing tensorboard or tensorboardx (17053)

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Contributors

awaelchli, belerico, carmocca, colehawkins, dmitsf, Erotemic, ethanwharris, kshitij12345, borda

_If we forgot someone due to not matching commit email with GitHub account, let us know :]_

App

Removed

- Removed implicit ui testing with `testing.run_app_in_cloud` in favor of headless login and app selection ([16741](https://github.com/Lightning-AI/lightning/pull/16741))

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Fabric

Added

- Added `Fabric(strategy="auto")` support ([16916](https://github.com/Lightning-AI/lightning/pull/16916))

Fixed

- Fixed edge cases in parsing device ids using NVML ([16795](https://github.com/Lightning-AI/lightning/pull/16795))
- Fixed DDP spawn hang on TPU Pods ([16844](https://github.com/Lightning-AI/lightning/pull/16844))
- Fixed an error when passing `find_usable_cuda_devices(num_devices=-1)` ([16866](https://github.com/Lightning-AI/lightning/pull/16866))

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PyTorch

Added

- Added `Fabric(strategy="auto")` support. It will choose DDP over DDP-spawn, contrary to `strategy=None` (default) ([16916](https://github.com/Lightning-AI/lightning/pull/16916))

Fixed

- Fixed DDP spawn hang on TPU Pods ([16844](https://github.com/Lightning-AI/lightning/pull/16844))
- Fixed edge cases in parsing device ids using NVML ([16795](https://github.com/Lightning-AI/lightning/pull/16795))
- Fixed backwards compatibility for `lightning.pytorch.utilities.parsing.get_init_args` ([16851](https://github.com/Lightning-AI/lightning/pull/16851))

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Contributors

ethanwharris, carmocca, awaelchli, justusschock , dtuit, Liyang90


_If we forgot someone due to not matching commit email with GitHub account, let us know :]_

App

Fixed

- Fixed `lightning open` command and improved redirects ([16794](https://github.com/Lightning-AI/lightning/pull/16794))

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Fabric

Fixed

- Fixed an issue causing a wrong environment plugin to be selected when `accelerator=tpu` and `devices > 1` ([16806](https://github.com/Lightning-AI/lightning/pull/16806))
- Fixed parsing of defaults for `--accelerator` and `--precision` in Fabric CLI when `accelerator` and `precision` are set to non-default values in the code ([16818](https://github.com/Lightning-AI/lightning/pull/16818))

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PyTorch

Fixed

- Fixed an issue causing a wrong environment plugin to be selected when `accelerator=tpu` and `devices > 1` ([16806](https://github.com/Lightning-AI/lightning/pull/16806))

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Contributors

ethanwharris, carmocca, awaelchli, borda, tchaton, yurijmikhalevich


_If we forgot someone due to not matching commit email with GitHub account, let us know :]_

App

Added

- Added Storage Commands ([16740](https://github.com/Lightning-AI/lightning/pull/16740))
* `rm`: Delete files from your Cloud Platform Filesystem
- Added `lightning connect data` to register data connection to private s3 buckets ([16738](https://github.com/Lightning-AI/lightning/pull/16738))

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Fabric

Fixed

- Fixed an attribute error and improved input validation for invalid strategy types being passed to Fabric ([16693](https://github.com/Lightning-AI/lightning/pull/16693))

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PyTorch

Changed

- Disabled strict loading in multiprocessing launcher ("ddp_spawn", etc.) when loading weights back into the main process ([16365](https://github.com/Lightning-AI/lightning/pull/16365))

Fixed

- Fixed an attribute error and improved input validation for invalid strategy types being passed to Trainer ([16693](https://github.com/Lightning-AI/lightning/pull/16693))
- Fixed early stopping triggering extra validation runs after reaching `min_epochs` or `min_steps` ([16719](https://github.com/Lightning-AI/lightning/pull/16719))


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Contributors

akihironitta, awaelchli, borda, tchaton

_If we forgot someone due to not matching commit email with GitHub account, let us know :]_

App

Added

- Added `lightning open` command (16482)
- Added experimental support for interruptable GPU in the cloud (16399)
- Added FileSystem abstraction to simply manipulate files (16581)
- Added Storage Commands (16606)
* `ls`: List files from your Cloud Platform Filesystem
* `cd`: Change the current directory within your Cloud Platform filesystem (terminal session based)
* `pwd`: Return the current folder in your Cloud Platform Filesystem
* `cp`: Copy files between your Cloud Platform Filesystem and local filesystem
- Prevent to `cd` into non-existent folders (16645)
- Enabled `cp` (upload) at project level (16631)
- Enabled `ls` and `cp` (download) at project level (16622)
- Added `lightning connect data` to register data connection to s3 buckets (16670)
- Added support for running with multiprocessing in the cloud (16624)
- Initial plugin server (16523)
- Connect and Disconnect node (16700)

Changed

- Changed the default `LightningClient(retry=False)` to `retry=True` (16382)
- Add support for async predict method in PythonServer and remove torch context (16453)
- Renamed `lightning.app.components.LiteMultiNode` to `lightning.app.components.FabricMultiNode` (16505)
- Changed the command `lightning connect` to `lightning connect app` for consistency (16670)
- Refactor cloud dispatch and update to new API (16456)
- Updated app URLs to the latest format (16568)

Fixed

- Fixed a deadlock causing apps not to exit properly when running locally (16623)
- Fixed the Drive root_folder not parsed properly (16454)
- Fixed malformed path when downloading files using `lightning cp` (16626)
- Fixed app name in URL (16575)

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Fabric

Fixed

- Fixed error handling for `accelerator="mps"` and `ddp` strategy pairing (16455)
- Fixed strict availability check for `torch_xla` requirement (16476)
- Fixed an issue where PL would wrap DataLoaders with XLA's MpDeviceLoader more than once (16571)
- Fixed the batch_sampler reference for DataLoaders wrapped with XLA's MpDeviceLoader (16571)
- Fixed an import error when `torch.distributed` is not available (16658)

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Pytorch

Fixed

- Fixed an unintended limitation for calling `save_hyperparameters` on mixin classes that don't subclass `LightningModule`/`LightningDataModule` (16369)
- Fixed an issue with `MLFlowLogger` logging the wrong keys with `.log_hyperparams()` (16418)
- Fixed logging more than 100 parameters with `MLFlowLogger` and long values are truncated (16451)
- Fixed strict availability check for `torch_xla` requirement (16476)
- Fixed an issue where PL would wrap DataLoaders with XLA's MpDeviceLoader more than once (16571)
- Fixed the batch_sampler reference for DataLoaders wrapped with XLA's MpDeviceLoader (16571)
- Fixed an import error when `torch.distributed` is not available (16658)

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Contributors

akihironitta, awaelchli, borda, BrianPulfer, ethanwharris, hhsecond, justusschock, Liyang90, RuRo, senarvi, shenoynikhil, tchaton

_If we forgot someone due to not matching commit email with GitHub account, let us know :]_