Is there a MySQL performance benchmark to measure the impact of utf8_unicode_ci versus utf8_general_ci?

Question

I read here and there that using the utf8_unicode_ci collation ensures a better treatment of unicode text (for example, it knowns how to expand characters such as 'œ' into 'oe' for searching and ordering) compared to the default utf8_general_ci which basically just strips diacritics. Unfortunately, both sources indicate that utf8_unicode_ci is slightly slower than utf8_general_ci.

So my question is: what does "slightly slower" mean? Has anyone run benchmarks? Are we talking about a -0.01% performance impact or rather something like -25%?

Thanks for your help.

Answer 1

I didn't see any benchmark, but you can run your own using the BENCHMARK function:

BENCHMARK(count,expr)

As advised by Matthew you may run a parallel installation of MYSQL, but consider that there could be a huge difference between different architecture (sparc, intel, 32bit, 64bit, ...).