"Previous exposure to a proper, modern GC" I've often heard people say things that imply that "proper" GC's don't behave like whatever badness I'm experiencing

"Previous exposure to a proper, modern GC" I've often heard people say things that imply that "proper" GC's don't behave like whatever badness I'm experiencing currently. Can you give me an example of a Garbage collector that I could safely use for a large heap of small cached (ie. long lifetimes) objects without a significant throughput penalty and with deterministic latencies (ie., no random full system pauses) over, say, a tcmalloc based hand-allocated/free'd system ?