Hacker News Reader

Exactly. You want memory arenas that are hot in this CPU's caches. If your thread moves, its per-thread caches are now elsewhere. Original TCMalloc was developed in the days of 2-4 core servers. Current TCMalloc was an evolution in the context of 32+ core servers.

View on HN

my feeling is that the space efficiency gains are probably more significant than the reduction in core migration costs. many applications have far more threads than the system has cores.

Sure, also true that the per-CPU scheme co-evolved with the proliferation of services with thread-per-request architectures having way more TIDs than cores.

Reply on news.ycombinator.com