What are the limits of branch prediction?

What are the limits of branch prediction?

Branch prediction is a technique used in CPUs to improve performance by guessing the direction of branch instructions. However, its limits include mispredictions, which can lead to performance penalties, and the inability to predict certain complex branching patterns.

Can you explain what happens during a misprediction?

During a misprediction, the CPU has to discard the speculatively executed instructions and revert to the correct path, which incurs a delay and can significantly impact performance.

Are there any techniques to improve branch prediction?

Yes, techniques like dynamic branch prediction, which uses historical data to make more accurate predictions, and hybrid predictors that combine multiple strategies can improve accuracy.

What are the real-world implications of branch prediction limits?

The limits of branch prediction can affect the overall efficiency of processors, impacting everything from mobile devices to high-performance computing, leading to slower execution times in critical applications.