It should be - the OS's whole job is to manage processes. I mean if it's allocating 4kb of physical memory to each then that would scale poorly, but who does that?
4KB is the size of a page on x86 and most architectures, the smallest unit of memory the OS can dispense. SSL termination is definitely a function you don't want the kernel to swap to disk, therefore each connection would get at least 4KB of physical memory under a process-per-connection model.