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I was reading through codeigniter documentation and they have a dedicated benchmarking class.

What is benchmarking used for in general ?
I searched the google but could not find examples of where and how benchmarking is used.

thanks

To see how fast different pieces of software are at performing the same task. Some benchmarks are for very specific operations; others attempt to do a variety of operations to emulate real-world workloads.

after this explanation - a re- read of the benchmarking class makes sense.
good to have one more tool at disposal