Memory alignment does matter (as shown, for example, for primitive array types in Java Tip 130), but I think it is unprofitable to chase after such low-level details.

Some of my array elements are very large numbers (i.e. 7000000000)? Does it have to allocate memory for each array element up to the maximum, even if they don't exist ...

Per-Åke Minborg, Consulting Member of Technical Staff, Java Core Libraries at Oracle, presented “Function and Memory Access in Pure Java” at JavaOne 2025. Minborg demonstrated how the Foreign ...

Memory pools are used to reuse existing memory blocks; you can use them to allocate memory blocks dynamically. Array pools manage a pool of arrays and rent them when asked for.