Comment by adgjlsfhk1
2 hours ago
You're wrong for like 6 different reasons.
Java does do bump pointer allocation. The key is that when GC runs, surviving objects get moved. The slow part of GC isn't the allocation (GCs generally have much faster allocators than malloc). The slow part is the barriers that the GC requires and the pauses.
You're wrong for like 6 different reasons.
If that were true you could have listed one the made sense in context. This person was saying that allocation was as fast as a incrementing a register while continually ignoring the fact that deallocation needs to happen along with any organization of allocated memory.
Then they were ignoring that large allocations have big speed benefits for a reason.
Conflating java moving a pointer, mapping memory into a process, sbrk, and arena allocation is going in circles, but the fundamentals that people need to fight the GC or work around it remains.
Allocations have a price and the first step to optimizing any program is avoiding that, but in GC languages you get pauses on top of your slow downs.