"..To briefly recap: the Cerebras Wafer Scale Cluster extends the 40GB of on-chip memory of each CS-2 with over 12 Terabytes of external memory. Unlike GPUs which only have 80GB of memory for all weights and activations, we store weights in external memory and activations in on-chip memory. The CS-2 works on one layer of the model at a time and weights are streamed in as needed, hence the name – Weight Streaming. This model provides us with over 100x larger aggregate memory capacity than GPUs, allowing us to natively support trillion parameter models without resorting to complex model partitioning schemes such as tensor and pipeline parallelism.