TOSS: Tiering of Serverless Snapshots for Memory-Efficient Serverless Computing
Theodore Michailidis, Juno Kim, Linsong Guo, Steven Swanson, Jishen Zhao · 2025
Serverless computing is an emerging cloud computing paradigm where users offload functions to serverless platforms that manage their own execution environments. Despite recent advancements on efficient serverless management, we find that cloud providers' solutions lead to unnecessary memory overheads, and significant memory cost by assuming a single tier of memory (DRAM). In this paper, we evaluate previous serverless works and offer insights about enabling memory tiering for serverless. Based on our insights, we introduce Tiering of Serverless Snapshots (TOSS), a heterogeneous memory mechanism that aims to reduce the total memory cost on serverless platforms, while achieving comparable performance to single-tier solutions. We show that TOSS achieves near optimal memory cost for most functions, while offloading on average 92% of the memory to the slow tier. In addition, TOSS achieves$52 \times$lower setup time and up to$4.2 \times$lower invocation time than the state-of-the-art DRAM-only mechanism.