bytedance/byteps

BytePS is a framework for training large AI models across many machines at the same time. Training modern AI models, especially large language models or image recognition systems, requires splitting the work across dozens or hundreds of graphics cards. BytePS handles the coordination between all those machines so that the training job runs as fast as possible. The core problem BytePS solves is communication. When many machines are each doing a piece of the training work, they need to constantly share updates with each other. The standard approach used by older tools was borrowed from supercomputing and works well when all machines are identical and the cluster is dedicated to a single job. Cloud environments are different: machines may have varying specs, they share infrastructure with other workloads, and network bandwidth is a precious resource. BytePS was redesigned from the ground up for this cloud-first reality. The result is a meaningful speed improvement. On a test involving a well-known language model trained across 256 graphics cards, BytePS achieved roughly 90% scaling efficiency, meaning each additional machine contributed close to its full potential. A competing tool called Horovod reached only about 70% efficiency on the same task. In cases where the network between machines is slower, BytePS can be twice as fast as the alternative. ByteDance, the company behind TikTok, built BytePS for its own internal AI workloads and then open-sourced it. It works with the most common AI training libraries: TensorFlow, PyTorch, Keras, and MXNet. Switching from Horovod to BytePS is intentionally simple: in most cases you change one import line and replace a prefix in your function calls. BytePS currently requires graphics cards and does not support training on regular processors alone. Features like fault tolerance (recovering gracefully if a machine crashes mid-training) are noted as not yet implemented but are on the project's roadmap.