This is why I saw microservices are "closer to the metal", i.e. they depend more on the physical characteristics of their environment than non-microservices. A

This is why I saw microservices are "closer to the metal", i.e. they depend more on the physical characteristics of their environment than non-microservices. A function call in a monolith can: * segfault * be called with the wrong number of parameters * call the wrong function * go through but never return * substitute itself with another function All of which are very similar to the RPC situation. However we practically never see this because of the OS guarantees like memory safety, security, etc, plus there are standardized ways of handling when these problems do occur, notably try / catch patterns. These issues can* be abstracted as well, but the advantage of scaling (being close to the metal) is the disadvantage as well (being very close to the hardware abstractions that let you scale). E.g., there is no difference between running a microservice on a scaling computer than guarantees memory access across a cluster with interrupts, etc (some millions of cpus and terabytes of memory), and running it on a bunch of instances, except the hardware. The former is exotic and abstracts the hardware, the later does not and so all these "low level" errors surface with great frequency.