Comment by cryptonector
4 years ago
POSIX doesn't require that fork() be implemented using copy-on-write techniques. An implementation is free to copy all of the parent's writable address space.
4 years ago
POSIX doesn't require that fork() be implemented using copy-on-write techniques. An implementation is free to copy all of the parent's writable address space.
An implementation of fork() that doesn't do CoW would have borderline unusable perf in many real-world scenarios.
If the parent is a JVM, for sure. But a copy-on-write fork() still doesn't perform well. The point isn't to just copy the whole parent. The point is to stop copying at all.