Systems that can reap no longer needed objects rather than walking them can help here. The automatic approach is a copy collector, which is typically the more o

Systems that can reap no longer needed objects rather than walking them can help here. The automatic approach is a copy collector, which is typically the more often approach of a generational garbage collector. Since a copy collector typically works by following references, this also increases data locality for machines with a small amount of L1 cache. Garbage Collectors and JITs typically work best with hardware support, as you need to check pointer reads and writes as objects are being moved around or code is being rewritten. A lot of these systems use MMU gymnastics, such as mapping the same memory page into multiple locations with different permissions. You also have systems where you create the objects knowing that they will be tiny and short-lived with a fixed lifetime, which can be hugely efficient. This is how Apache Bucket brigades work, since they know that other than a few special cases all memory allocated while handling a request will be garbage once a response is returned.