slipstream
SlipStream: Adapting Pipelines for Distributed Training of Large DNNs Amid Failures
Gandhi, Swapnil, Zhao, Mark, Skiadopoulos, Athinagoras, Kozyrakis, Christos
Training large Deep Neural Network (DNN) models requires thousands of GPUs for days or weeks at a time. At these scales, failures are frequent and can have a big impact on training throughput. Restoring performance using spare GPU servers becomes increasingly expensive as models grow. SlipStream is a system for efficient DNN training in the presence of failures, without using spare servers. It exploits the functional redundancy inherent in distributed training systems -- servers hold the same model parameters across data-parallel groups -- as well as the bubbles in the pipeline schedule within each data-parallel group. SlipStream dynamically re-routes the work of a failed server to its data-parallel peers, ensuring continuous training despite multiple failures. However, re-routing work leads to imbalances across pipeline stages that degrades training throughput. SlipStream introduces two optimizations that allow re-routed work to execute within bubbles of the original pipeline schedule. First, it decouples the backward pass computation into two phases. Second, it staggers the execution of the optimizer step across pipeline stages. Combined, these optimizations enable schedules that minimize or even eliminate training throughput degradation during failures. We describe a prototype for SlipStream and show that it achieves high training throughput under multiple failures, outperforming recent proposals for fault-tolerant training such as Oobleck and Bamboo by up to 1.46x and 1.64x, respectively.
Accelerating Recommender Model Training by Dynamically Skipping Stale Embeddings
Maboud, Yassaman Ebrahimzadeh, Adnan, Muhammad, Mahajan, Divya, Nair, Prashant J.
Training recommendation models pose significant challenges regarding resource utilization and performance. Prior research has proposed an approach that categorizes embeddings into popular and non-popular classes to reduce the training time for recommendation models. We observe that, even among the popular embeddings, certain embeddings undergo rapid training and exhibit minimal subsequent variation, resulting in saturation. Consequently, updates to these embeddings lack any contribution to model quality. This paper presents Slipstream, a software framework that identifies stale embeddings on the fly and skips their updates to enhance performance. This capability enables Slipstream to achieve substantial speedup, optimize CPU-GPU bandwidth usage, and eliminate unnecessary memory access. SlipStream showcases training time reductions of 2x, 2.4x, 1.2x, and 1.175x across real-world datasets and configurations, compared to Baseline XDL, Intel-optimized DRLM, FAE, and Hotline, respectively.
Sony's AI can employ clever strategies to beat the best humans at 'Gran Turismo' - SiliconANGLE
Sony Corp. announced today that it has created an artificial intelligence that can get the better of humans when playing the simulation game "Gran Turismo," which could have implications in the future for self-driving technology. AI has already mastered such games as "Go" and chess, and according to Sony, it took just two days of training for the technology Gran Turismo Sophy or GT Sophy to leave human players in the dust. At the two-day mark it was beating 95% of the best human players, and in the following days kept shaving time from its previous results. Sony said the AI mastered a number of tracks, not only by figuring out when to slow down or accelerate but using tactics such as when the time is right to get in behind a car and use the slipstream. When it became obvious that the car wasn't using a good racing line, it would change to another line.