> Out of memory means, your system is simply not designed for the task at hand.

Speaking as somebody who's never built such a system, wouldn't maintaining some opportunistic cache (e.g. for some space-time-tradeoff) be a valid use case of asking for more memory and gracefully degrading in case it's not available?

Error handling would simply consist of not expanding the cache size (if it happens during an allocation related to the cache) or freeing up some cache memory (if it happens for an essential allocation).