一句话：提出首个无需对比其他分配器即可定位分配器所致性能下降的 profiler，基于堆对象生命周期区分慢管理与慢访问。
现有剖析器无法定位内存分配器导致的性能下降，程序员可能徒劳优化应用代码。MemPerf 是首个无需与其他分配器对比即可识别此类下降的剖析器。它基于分配器影响堆对象整个生命周期（含对象访问）这一观察，分别检测慢内存管理操作与慢访问：前者采用线程感知和类型感知的性能建模，后者用自顶向下方法识别 cache/TLB 未命中等由分配器引入的原因，并统一高效定位。评估中，MemPerf 对大于 5% 的中大型分配器减速报告正确率达 98%，无误报，并揭示广泛使用分配器中的多个已知和未知设计问题。
The memory allocator plays a key role in the performance of applications, but none of the existing profilers can pinpoint performance slowdowns caused by a memory allocator. Consequently, programmers may spend time improving application code incorrectly or unnecessarily, achieving low or no performance improvement. This paper designs the first profiler—MemPerf—to identify allocator-induced performance slowdowns without comparing against another allocator. Based on the key observation that an allocator may impact the whole life-cycle of heap objects, including the accesses (or uses) of these objects, MemPerf proposes a life-cycle based detection to identify slowdowns caused by slow memory management operations and slow accesses separately. For the prior one, MemPerf proposes a thread-aware and type-aware performance modeling to identify slow management operations. For slow memory accesses, MemPerf utilizes a top-down approach to identify all possible reasons for slow memory accesses introduced by the allocator, mainly due to cache and TLB misses, and further proposes a unified method to identify them correctly and efficiently. Based on our extensive evaluation, MemPerf reports 98% medium and large allocator-reduced slowdowns (larger than 5%) correctly without reporting any false positives. MemPerf also pinpoints multiple known and unknown design issues in widely-used allocators.
@article{paperbot1875,
title = {MemPerf: Profiling Allocator-Induced Performance Slowdowns},
author = {Jin Zhou and Sam Silvestro and Steven (Jiaxun) Tang and Hanmei Yang and Hongyu Liu and Guangming Zeng and Bo Wu and Cong Liu and Tongping Liu},
journal = {Proceedings of the ACM on Programming Languages},
volume = {7},
number = {OOPSLA2},
year = {2023},
doi = {10.1145/3622848}
}