Changelog¶

All notable changes to this project will be documented in this file.

The format is based on Keep a Changelog.

[2.1.0] - 2023-10-11¶

[2.1.0] - Added¶

Added support for the TPU-v4 architecture (#17227)
Added support for XLA’s new PJRT runtime (#17352)
Added support for Fully Sharded Data Parallel (FSDP) training with XLA (#18126, #18424, #18430)
Check for invalid TPU device inputs (#17227)
Added XLAStrategy(sync_module_states=bool) to control whether to broadcast the parameters to all devices (#17522)
Added support for joint setup of model and optimizer with FSDP (#17305)
Added support for handling multiple parameter groups in optimizers set up with FSDP (#17305)
Added support for saving and loading sharded model and optimizer state with FSDPStrategy (#17323)
Added a warning when calling methods on _FabricModule that bypass the strategy-specific wrappers (#17424)
Added Fabric.init_tensor() context manager to instantiate tensors efficiently directly on device and dtype (#17488)
Added Fabric.init_module() context manager to instantiate large models efficiently directly on device, dtype, and with sharding support (#17462)
- Creates the model parameters in the desired dtype (torch.float32, torch.float64, torch.float16, or torch.bfloat16) depending on the ‘true’ precision choice in Fabric(precision='32-true'|'64-true'|'16-true'|'bf16-true')
- Handles initialization for FSDP models before wrapping and the Zero stage 3 initialization for DeepSpeed before sharding
Added support for empty weight initialization with Fabric.init_module(empty_init=True) for checkpoint loading (#17627)
Added support for meta-device initialization with Fabric.init_module(empty_init=True) in FSDP (#18122)
Added lightning.fabric.plugins.Precision.module_init_context() and lightning.fabric.strategies.Strategy.module_init_context() context managers to control model and tensor instantiation (#17462)
lightning.fabric.strategies.Strategy.tensor_init_context() context manager to instantiate tensors efficiently directly on device and dtype (#17607)
Run the DDP wrapper in a CUDA stream (#17334)
Added support for true half-precision as Fabric(precision="16-true"|"bf16-true") (#17287)
Added support for mixed 8-bit precision as Fabric(precision="transformer-engine") using Nvidia’s Transformer Engine (#17597)
Added support for linear layer quantization with Fabric(plugins=BitsandbytesPrecision()) using bitsandbytes (#18655)
Added error messaging for missed .launch() when it is required (#17570)
Added support for saving checkpoints with either full state-dict or sharded state dict via FSDPStrategy(state_dict_type="full"|"sharded") (#17526)
Added support for loading a full-state checkpoint file into a sharded model (#17623)
Added support for calling hooks on a LightningModule via Fabric.call (#17874)
Added the parameter Fabric.load(..., strict=True|False) to enable non-strict loading of partial checkpoint state (#17645)
Added the parameter Fabric.save(..., filter=...) to enable saving a partial checkpoint state (#17845)
Added support for loading optimizer states from a full-state checkpoint file (#17747)
Automatically call xla_model.mark_step() before saving checkpoints with XLA (#17882)
Automatically call xla_model.mark_step() after optimizer.step() with XLA (#17883)
Added support for all half-precision modes in FSDP precision plugin (#17807)
Added FSDPStrategy(activation_checkpointing_policy=...) to customize the layer policy for automatic activation checkpointing (requires torch>=2.1) (#18045)
Added a callback for spike-detection (#18014)
Added the ability to set the torch.distributed.fsdp.ShardingStrategy via string in FSDPStrategy (#18087)
Improved error messages when attempting to load a DeepSpeed checkpoint at an invalid path (#17795)
Added Fabric.load_raw() for loading raw PyTorch state dict checkpoints for model or optimizer objects (#18049)
Allowed accessing rank information in the main process before processes are launched when using the XLAStrategy (#18194)
Added automatic process cleanup to avoid zombie child processes and stalls when exceptions are raised (#18218)
Added validation of user input for devices and num_nodes when running with SLURM or TorchElastic (#18292)
Improved the error messaging and instructions when handling custom batch samplers in distributed settings (#18402)
Added support for saving and loading stateful objects other than modules and optimizers (#18513)
Enabled the default process group configuration for FSDP’s hybrid sharding (#18583)
Added lightning.fabric.utilities.suggested_max_num_workers to assist with setting a good value in distributed settings (#18591)
Added lightning.fabric.utilities.is_shared_filesystem utility function to automatically check whether the filesystem is shared between machines (#18586)
Removed support for PyTorch 1.11 (#18691)
Added support for passing the argument .load_state_dict(..., assign=True|False) on Fabric-wrapped modules in PyTorch 2.1 or newer (#18690)

[2.1.0] - Changed¶

Allow using iterable-style datasets with TPUs (#17331)
Increased the minimum XLA requirement to 1.13 (#17368)
Fabric argument validation now only raises an error if conflicting settings are set through the CLI (#17679)
DataLoader re-instantiation is now only performed when a distributed sampler is required (#18191)
Improved the formatting of emitted warnings (#18288)
Broadcast and reduction of tensors with XLA-based strategies now preserve the input’s device (#18275)
Due to lack of reliability, Fabric now only runs on one GPU instead of all GPUs in a Jupyter notebook if devices="auto" (default) (#18291)
Enabled launching via torchrun in a SLURM environment; the TorchElasticEnvironment now gets chosen over the SLURMEnvironment if both are detected (#18618)
If not set by the user, Lightning will set OMP_NUM_THREADS to num_cpus / num_processes when launching subprocesses (e.g. when DDP is used) to avoid system overload for CPU-intensive tasks (#18677)

[2.1.0] - Deprecated¶

Deprecated the DDPStrategy.is_distributed property. This strategy is distributed by definition (#17381)
Deprecated the SingleTPUStrategy (strategy="single_tpu") in favor of SingleDeviceXLAStrategy (strategy="single_xla") (#17383)
Deprecated the TPUAccelerator in favor of XLAAccelerator (#17383)
Deprecated the TPUPrecision in favor of XLAPrecision (#17383)
Deprecated the TPUBf16Precision in favor of XLABf16Precision (#17383)

[2.1.0] - Removed¶

Removed automatic sharding support with Fabric.run or using fabric.launch(fn). This only impacts FSDP and DeepSpeed strategy users. Please instantiate your module under the newly added fabric.init_module context manager (#17832)
Removed the unsupported checkpoint_io argument from the FSDPStrategy (#18192)

[2.1.0] - Fixed¶

Fixed issue where running on TPUs would select the wrong device index (#17227)
Removed the need to call .launch() when using the DP-strategy (strategy="dp") (#17931)
Fixed FSDP re-applying activation checkpointing when the user had manually applied it already (#18006)
Fixed FSDP re-wrapping the module root when the user had manually wrapped the model (#18054)
Fixed issue where unexpected exceptions would leave the default torch dtype modified when using true precision settings (#18500)
Fixed redundant input-type casting in FSDP precision (#18630)
Fixed an issue with find_usable_cuda_devices(0) incorrectly returning a list of devices (#18722)
Fixed redundant file writes in CSVLogger (#18567)

[2.0.9] - 2023-09-14¶

[2.0.9] - Fixed¶

Fixed an issue causing the _FabricOptimizer.state to remain outdated after loading with load_state_dict (#18488)

[2.0.8] - 2023-08-29¶

[2.0.8] - Changed¶

On XLA, avoid setting the global rank before processes have been launched as this will initialize the PJRT computation client in the main process (#16966)

[2.0.8] - Fixed¶

Fixed model parameters getting shared between processes when running with strategy="ddp_spawn" and accelerator="cpu"; this has a necessary memory impact, as parameters are replicated for each process now (#18238)
Removed false positive warning when using fabric.no_backward_sync with XLA strategies (#17761)
Fixed issue where Fabric would not initialize the global rank, world size, and rank-zero-only rank after initialization and before launch (#16966)
Fixed FSDP full-precision param_dtype training (16-mixed, bf16-mixed and 32-true configurations) to avoid FSDP assertion errors with PyTorch < 2.0 (#18278)

[2.0.7] - 2023-08-14¶

[2.0.7] - Changed¶

Disabled the auto-detection of the Kubeflow environment (#18137)

[2.0.7] - Fixed¶

Fixed issue where DDP subprocesses that used Hydra would set hydra’s working directory to current directory (#18145)
Fixed an issue that would prevent the user to set the multiprocessing start method after importing lightning (#18177)
Fixed an issue with Fabric.all_reduce() not performing an inplace operation for all backends consistently (#18235)

[2.0.6] - 2023-07-20¶

[2.0.6] - Fixed¶

Fixed TensorBoardLogger.log_graph not unwrapping the _FabricModule (#17844)

[2.0.5] - 2023-07-07¶

[2.0.5] - Added¶

Added validation against misconfigured device selection when using the DeepSpeed strategy (#17952)

[2.0.5] - Changed¶

Avoid info message when loading 0 entry point callbacks (#17990)

[2.0.5] - Fixed¶

Fixed the emission of a false-positive warning when calling a method on the Fabric-wrapped module that accepts no arguments (#17875)
Fixed check for FSDP’s flat parameters in all parameter groups (#17914)
Fixed automatic step tracking in Fabric’s CSVLogger (#17942)
Fixed an issue causing the torch.set_float32_matmul_precision info message to show multiple times (#17960)
Fixed loading model state when Fabric.load() is called after Fabric.setup() (#17997)

[2.0.4] - 2023-06-22¶

[2.0.4] - Fixed¶

Fixed validation of parameters of plugins.precision.MixedPrecision (#17687)
Fixed an issue with hpu imports leading to performance degradation (#17788)
Fixed computing the next version folder in CSVLogger (#17139, #17139)

[2.0.3] - 2023-06-07¶

Added support for Callback registration through entry points (#17756)

[2.0.3] - Changed¶

Made type hints public (#17100)
Support compiling a module after it was set up by Fabric (#17529)

[2.0.3] - Fixed¶

Fixed computing the next version folder in CSVLogger (#17139)
Fixed inconsistent settings for FSDP Precision (#17670)

[2.0.2] - 2023-04-24¶

[2.0.2] - Changed¶

Enabled precision autocast for LightningModule step methods in Fabric (#17439)

[2.0.2] - Fixed¶

Fixed an issue with LightningModule.*_step methods bypassing the DDP/FSDP wrapper (#17424)
Fixed device handling in Fabric.setup() when the model has no parameters (#17441)

[2.0.1] - 2023-03-30¶

[2.0.1] - Changed¶

Generalized Optimizer validation to accommodate both FSDP 1.x and 2.x (#16733)

[2.0.0] - 2023-03-15¶

[2.0.0] - Added¶

Added Fabric.all_reduce (#16459)
Added support for saving and loading DeepSpeed checkpoints through Fabric.save/load() (#16452)
Added support for automatically calling set_epoch on the dataloader.batch_sampler.sampler (#16841)
Added support for writing logs to remote file systems with the CSVLogger (#16880)
Added support for frozen dataclasses in the optimizer state (#16656)
Added lightning.fabric.is_wrapped to check whether a module, optimizer, or dataloader was already wrapped by Fabric (#16953)

[2.0.0] - Changed¶

Fabric now chooses accelerator="auto", strategy="auto", devices="auto" as defaults (#16842)
Checkpoint saving and loading redesign (#16434)
- Changed the method signatrue of Fabric.save and Fabric.load
- Changed the method signature of Strategy.save_checkpoint and Fabric.load_checkpoint
- Fabric.save accepts a state that can contain model and optimizer references
- Fabric.load can now load state in-place onto models and optimizers
- Fabric.load returns a dictionary of objects that weren’t loaded into the state
- Strategy.save_checkpoint and Fabric.load_checkpoint are now responsible for accessing the state of the model and optimizers
DataParallelStrategy.get_module_state_dict() and DDPStrategy.get_module_state_dict() now correctly extracts the state dict without keys prefixed with ‘module’ (#16487)
“Native” suffix removal (#16490)
- strategy="fsdp_full_shard_offload" is now strategy="fsdp_cpu_offload"
- lightning.fabric.plugins.precision.native_amp is now lightning.fabric.plugins.precision.amp
Enabled all shorthand strategy names that can be supported in the CLI (#16485)
Renamed strategy='tpu_spawn' to strategy='xla' and strategy='tpu_spawn_debug' to strategy='xla_debug' (#16781)
Changed arguments for precision settings (from [64|32|16|bf16] to [“64-true”|”32-true”|”16-mixed”|”bf16-mixed”]) (#16767)
The selection Fabric(strategy="ddp_spawn", ...) no longer falls back to “ddp” when a cluster environment gets detected (#16780)
Renamed setup_dataloaders(replace_sampler=...) to setup_dataloaders(use_distributed_sampler=...) (#16829)

[2.0.0] - Removed¶

Removed support for PyTorch 1.10 (#16492)
Removed support for Python 3.7 (#16579)

[2.0.0] - Fixed¶

Fixed issue where the wrapped dataloader iter() would be called twice (#16841)
Improved the error message for installing tensorboard or tensorboardx (#17053)

[1.9.4] - 2023-03-01¶

[1.9.4] - Added¶

Added Fabric(strategy="auto") support (#16916)

[1.9.4] - Fixed¶

Fixed edge cases in parsing device ids using NVML (#16795)
Fixed DDP spawn hang on TPU Pods (#16844)
Fixed an error when passing find_usable_cuda_devices(num_devices=-1) (#16866)

[1.9.3] - 2023-02-21¶

[1.9.3] - Fixed¶

Fixed an issue causing a wrong environment plugin to be selected when accelerator=tpu and devices > 1 (#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)

[1.9.2] - 2023-02-15¶

[1.9.2] - Fixed¶

Fixed an attribute error and improved input validation for invalid strategy types being passed to Trainer (#16693)

[1.9.1] - 2023-02-10¶

[1.9.1] - 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)

[1.9.0] - 2023-01-17¶

[1.9.0] - Added¶

Added Fabric.launch() to programmatically launch processes (e.g. in Jupyter notebook) (#14992)
Added the option to launch Fabric scripts from the CLI, without the need to wrap the code into the run method (#14992)
Added Fabric.setup_module() and Fabric.setup_optimizers() to support strategies that need to set up the model before an optimizer can be created (#15185)
Added support for Fully Sharded Data Parallel (FSDP) training in Lightning Lite (#14967)
Added lightning.fabric.accelerators.find_usable_cuda_devices utility function (#16147)
Added basic support for LightningModules (#16048)
Added support for managing callbacks via Fabric(callbacks=...) and emitting events through Fabric.call() (#16074)
Added Logger support (#16121)
- Added Fabric(loggers=...) to support different Logger frameworks in Fabric
- Added Fabric.log for logging scalars using multiple loggers
- Added Fabric.log_dict for logging a dictionary of multiple metrics at once
- Added Fabric.loggers and Fabric.logger attributes to access the individual logger instances
- Added support for calling self.log and self.log_dict in a LightningModule when using Fabric
- Added access to self.logger and self.loggers in a LightningModule when using Fabric
Added lightning.fabric.loggers.TensorBoardLogger (#16121)
Added lightning.fabric.loggers.CSVLogger (#16346)
Added support for a consistent .zero_grad(set_to_none=...) on the wrapped optimizer regardless of which strategy is used (#16275)

[1.9.0] - Changed¶

Renamed the class LightningLite to Fabric (#15932, #15938)
The Fabric.run() method is no longer abstract (#14992)
The XLAStrategy now inherits from ParallelStrategy instead of DDPSpawnStrategy (#15838)
Merged the implementation of DDPSpawnStrategy into DDPStrategy and removed DDPSpawnStrategy (#14952)
The dataloader wrapper returned from .setup_dataloaders() now calls .set_epoch() on the distributed sampler if one is used (#16101)
Renamed Strategy.reduce to Strategy.all_reduce in all strategies (#16370)
When using multiple devices, the strategy now defaults to “ddp” instead of “ddp_spawn” when none is set (#16388)

[1.9.0] - Removed¶

Removed support for FairScale’s sharded training (strategy='ddp_sharded'|'ddp_sharded_spawn'). Use Fully-Sharded Data Parallel instead (strategy='fsdp') (#16329)

[1.9.0] - Fixed¶

Restored sampling parity between PyTorch and Fabric dataloaders when using the DistributedSampler (#16101)
Fixes an issue where the error message wouldn’t tell the user the real value that was passed through the CLI (#16334)

[1.8.6] - 2022-12-21¶

minor cleaning

[1.8.5] - 2022-12-15¶

minor cleaning

[1.8.4] - 2022-12-08¶

[1.8.4] - Fixed¶

Fixed shuffle=False having no effect when using DDP/DistributedSampler (#15931)

[1.8.3] - 2022-11-22¶

[1.8.3] - Changed¶

Temporarily removed support for Hydra multi-run (#15737)

[1.8.2] - 2022-11-17¶

[1.8.2] - Fixed¶

Fixed the automatic fallback from LightningLite(strategy="ddp_spawn", ...) to LightningLite(strategy="ddp", ...) when on an LSF cluster (#15103)

[1.8.1] - 2022-11-10¶

[1.8.1] - Fixed¶

Fix an issue with the SLURM srun detection causing permission errors (#15485)
Fixed the import of lightning_lite causing a warning ‘Redirects are currently not supported in Windows or MacOs’ (#15610)