interface Deno.MemoryUsage
rss: numberThe number of bytes of the current Deno's process resident set size, which is the amount of memory occupied in main memory (RAM).
heapTotal: numberThe total size of the heap for V8, in bytes.
heapUsed: numberThe amount of the heap used for V8, in bytes.
external: numberMemory, in bytes, associated with JavaScript objects outside of the JavaScript isolate.