Optimizing Memory Mapping Using Deep Reinforcement Learning
Authors: name: Pengming Wang, name: Mikita Sazanovich, name: Berkin Ilbeyi, name: Phitchaya Mangpo Phothilimthana, name: Manish Purohit, name: Han Yang Tay, name: Ngân Vũ, name: Miaosen Wang, name: Cosmin Paduraru, name: Edouard Leurent, name: Anton Zhernov, name: Julian Schrittwieser, name: Thomas Hubert, name: Robert Tung, name: Paula Kurylowicz, name: Kieran Milan, name: Oriol Vinyals, name: Daniel J. Mankowitz

Resource scheduling and allocation is a critical component of many high
impact systems ranging from congestion control to cloud computing. Finding more
optimal solutions to these problems often has significant impact on resource
and time savings, reducing device wear-and-tear, and even potentially improving
carbon emissions. In this paper, we focus on a specific instance of a
scheduling problem, namely the memory mapping problem that occurs during
compilation of machine learning programs: That is, mapping tensors to different
memory layers to optimize execution time.
  We introduce an approach for solving the memory mapping problem using
Reinforcement Learning. RL is a solution paradigm well-suited for sequential
decision making problems that are amenable to planning, and combinatorial
search spaces with high-dimensional data inputs. We formulate the problem as a
single-player game, which we call the mallocGame, such that high-reward
trajectories of the game correspond to efficient memory mappings on the target
hardware. We also introduce a Reinforcement Learning agent, mallocMuZero, and
show that it is capable of playing this game to discover new and improved
memory mapping solutions that lead to faster execution times on real ML
workloads on ML accelerators. We compare the performance of mallocMuZero to the
default solver used by the Accelerated Linear Algebra (XLA) compiler on a
benchmark of realistic ML workloads. In addition, we show that mallocMuZero is
capable of improving the execution time of the recently published AlphaTensor
matrix multiplication model.