bearophile wrote:
You are right. It's not easy to give average numbers for any kind of C or C++ software. In benchmark-like code I've seen up to 20-25% improvements, but I assume that in much larger programs the situation is different. Probably if you try to compute a true average, the average percentage of improvement is lower, like 5% or less. It's a feature useful for hot spots of the code.
Small benchmarks tend to have a high 'beta', or variance from the norm. The results in actual applications tend to be much closer together.
