JavaScript GC: Pauses, Allocation Rate, Frontend Jank

Random 30–50ms freezes with no obvious long tasks in the Performance panel often have one root cause: the garbage collector. V8 pauses JavaScript execution to reclaim memory, and if your allocation rate is high enough, those pauses happen frequently — creating jank that shows up as a sawtooth pattern in the memory timeline rather than a spike in the flame chart. What this covers: How V8's generational garbage collector works (minor vs major GC), why allocation rate matters more than total alloca