A metric the test uses to record information about CPU activity during a performance test.
- Xcode 11.0+
XCTCPUMetric captures the following statistics about CPU activity; each metric is captured while the block argument to a
measure call runs in a performance test:
CPU time is the length of time, in seconds, that the CPU is active and executing instructions for the measured target. When the CPU switches context to execute a different process or thread or becomes idle, this value doesn't increase.
CPU cycles is the number of clock cycles that occur while the CPU is active and executing instructions for the measured target.
CPU instructions retired is the number of processor instructions that run to completion during execution of the measured target. It's possible for a CPU to abandon processing an instruction during execution, for example, if the instruction is evaluated out of order and logically follows a branch in the code that the CPU discovers it doesn’t need to take. An abandoned instruction doesn’t contribute to the retired instructions metric.