Wait for project Valhalla to be completed and turn the class into a value class.
OK, that's not 100% seriously, but when we do get it, we can have a lot of performance improvements if applied correctly. A quick example:
@ 40:22 (also check out the Loom example @ 19:10). Summarising the video: by adding one word (public class -> public value class) the example had a memory footprint of 4MB instead of 4GB (and a speed increase of 4s -> 290ms as well).