Calling fork() does not duplicate a process's memory space; it copies the page table hierarchy and sets every Page Table Entry to read-only. When either process attempts a write, the hardware MMU triggers a page fault exception, forcing the Linux kernel to allocate a new physical page, replicate the data via memcpy, and broadcast TLB shootdowns across CPU cores. High-throughput in-memory workloads encounter severe write amplification, elevated latency, and unexpected Out-of-Memory terminations. ...