Why is it possible that the combined processes CPU usage is higher than the total CPU usage, as reported by top?
It is indeed possible for the combined CPU usage of multiple processes to appear higher than the total CPU usage reported by system monitoring tools like `top`. This can happen due to several reasons: 1. **Measurement Overhead**: System monitoring tools like `top` can introduce some measurement overhead. They periodically sample CPU usage for each process, and there might be a slight delay between samples. During this delay, processes can use CPU cycles without being accounted for in the total CPU usage. 2. **Multicore and Hyper-Threading**: Modern CPUs have multiple cores and, in some cases, hyper-threading technology. The total CPU usage reported by `top` typically represents the aggregate usage of all CPU cores. If a process is heavily multi-threaded or uses multiple CPU cores efficiently, it can saturate the CPU cores, causing the total usage to appear lower. 3. **I/O and Waiting**: Processes can spend time waiting for I/O operations (e.g., reading/writing data to disk) or other r