一句话：提出 Wax，用调试与源码信息让过期 profile 仍可有效指导数据中心应用的二进制布局优化并显著加速。
数据中心应用的指令足迹庞大，会压垮 I-cache、iTLB 和 BTB 等片上结构，造成频繁前端停顿。现有做法依赖 profile-guided optimization，按少量热路径重排二进制布局；但生产环境中通常只能用旧版本 profile 优化新版本二进制，导致大量 profile 过期失效。Wax 的核心思想是在用过期 profile 优化新二进制时结合 debug 与源码信息，从而更准确地将旧 profile 对应到新代码并指导布局重排。作者在 5 个数据中心应用上评估，Wax 取得 5.76%–26.46% 的加速，比当时最优方法多 1.20%–7.86%，并达到 fresh profile 收益的 65%–93%。
Data center applications' large instruction footprints cause frequent front-end stalls by overwhelming on-chip micro-architectural structures such as instruction cache (I-cache), instruction translation look-aside buffer (iTLB), and branch target buffer (BTB). To reduce pressure on these structures, data center providers leverage profile-guided optimizations by reordering binary layout along a relatively small number of hot code paths. Such reordering provides the highest benefit if profile collection and optimization happen on the same version of the binary. In practice, companies have to optimize and deploy a fresh version of the binary with a profile from a previous version, making a large fraction of the profile stale. In this paper, we propose Wax. We open source our work at https://github.com/ice-rlab/wax, a novel technique to optimize data center applications with stale profiles. Wax's key insight is to leverage the debug and source code information while optimizing fresh binaries with stale profiles. We evaluate Wax for 5 data center applications to show that Wax provides significant (5.76%-26.46%) performance speedups. Wax achieves 1.20%-7.86% greater speedups than the state of the art, obtaining 65%-93% of fresh profiles' benefits.
@inproceedings{BhuiyanHMK26,
title = {<scp>Wax:</scp>
Optimizing Data Center Applications With Stale Profile},
author = {Tawhid Bhuiyan and Sumya Hoque and Angélica Aparecida Moreira and Tanvir Ahmed Khan},
booktitle = {ASPLOS},
year = {2026},
doi = {10.1145/3779212.3790248}
}