Long Context gpt-oss Training | Unsloth Documentation

We’re excited to introduce Unsloth Flex Attention support for OpenAI gpt-oss training that enables >8× longer context lengths, >50% less VRAM usage and >1.5× faster training (with no accuracy degradation) vs. all implementations including those using Flash Attention 3 (FA3). Unsloth Flex Attention makes it possible to train with a 60K context length on a 80GB VRAM H100 GPU for BF16 LoRA. Also: You