Google CS: Memory Management & Go Slices Interview

This question tests core memory management concepts across operating systems and language runtimes. You'll be expected to explain virtual memory and how address translation works end-to-end (logical → physical addresses), including page tables, multi-level tables, and the role of the TLB. Describe paging as a mechanism, why it helps with isolation and efficient use of RAM, and what triggers a page fault and how the OS handles it.

Expect a typical interview flow: first, define virtual memory, paging, and page faults; next, walk through address translation and page table formats; then discuss page replacement policies (LRU, FIFO, CLOCK) and performance trade-offs; finally, cover language-level memory details—specifically Go slices. For Go slices show the slice header (pointer, length, capacity), how append can reallocate the underlying array, implications for aliasing and performance, and when copies occur.

Skills you should demonstrate: systems-level thinking (address translation, page faults, TLB behavior), OS knowledge (page replacement, fragmentation, allocation), and language/runtime insight (Go slices memory layout, GC/allocator interactions, copy-on-write considerations). Be ready to reason about optimizations (reducing page faults, minimizing fragmentation, prefetching, using contiguous allocations) and to draw diagrams or write short pseudo-code to clarify your approach.