eWAPA: An eBPF-based WASI Performance Analysis Framework for WebAssembly Runtimes

TL;DR

This paper introduces eWAPA, a framework using eBPF to analyze WebAssembly System Interface (WASI) performance, helping optimize runtime efficiency by detailed metrics collection and anomaly analysis.

Contribution

It presents a novel eBPF-based framework for detailed performance analysis of WASI, addressing the gap in understanding runtime-OS interactions and anomalies.

Findings

Collected key performance metrics under various I/O loads

Identified causes of two specific WASI performance anomalies

Provided insights for optimizing WASI runtime implementations

Abstract

WebAssembly (Wasm) is a low-level bytecode format that can run in modern browsers. With the development of standalone runtimes and the improvement of the WebAssembly System Interface (WASI), Wasm has further provided a more complete sandboxed runtime experience for server-side applications, effectively expanding its application scenarios. However, the implementation of WASI varies across different runtimes, and suboptimal interface implementations can lead to performance degradation during interactions between the runtime and the operating system. Existing research mainly focuses on overall performance evaluation of runtimes, while studies on WASI implementations are relatively scarce. To tackle this problem, we propose an eBPF-based WASI performance analysis framework. It collects key performance metrics of the runtime under different I/O load conditions, such as total execution time, startup time, WASI execution time, and syscall time. We can comprehensively analyze the performance of the runtime's I/O interactions with the operating system. Additionally, we provide a detailed analysis of the causes behind two specific WASI performance anomalies. These analytical results will guide the optimization of standalone runtimes and WASI implementations, enhancing their efficiency.