intermediate · multicore
Does Hyper-Threading Double Your Cores?
A machine reports 32 logical CPUs but has 16 physical cores. Do you have 32 cores worth of compute?
Practical scenario
A service configures its worker pool from the reported CPU count. On a new instance type that number doubled, throughput did not, and tail latency got worse.
What it tests
- • Whether the candidate distinguishes logical from physical execution resources
- • Understanding of why SMT exists at all
- • Awareness that SMT can reduce performance for some workloads