What problem does it solve? Pretraining large language models from scratch requires coordinating complex distributed training strategies across hundreds of GPUs, and configuring FSDP, tensor parallelism, pipeline parallelism, and Float8 quantization correctly is error-prone and time-consuming. ## Core Features & Use Cases - 4D Parallelism Configuration: Compose FSDP2, tensor parallelism, pipeline parallelism, and context parallelism to scale training from 8 to 512+ GPUs for models like Llama 3.1 8B through 405B. - Float8 and torch.compile Optimization: Enable Float8 training with torchao and torch.compile for up to 48% throughput gains on H100 GPUs. - Checkpoint Management: Use distributed checkpointing with async saves, HuggingFace conversion, and seed checkpoints for pipeline parallelism. - Use Case: A research team wants to pretrain a Llama 3.1 70B model on 256 GPUs across 32 SLURM-managed nodes. This Skill provides the TOML configuration, SLURM script, and parallelism settings to launch and monitor the run. ## Quick Start Ask the AI to configure and launch a TorchTitan pretraining run for Llama 3.1 8B on 8 GPUs with a TOML config file.