The current leaders are on my smhasher site, https://github.com/rurban/smhasher/
I'm asking for an apples-to-apples comparison here. Using one figure from a random CPU on github and comparing it to another figure from a different random CPU on github is not an apples to apples comparison.
I don't think anyone claimed xxhash would be 5x faster than metrohash. (Maybe you are getting the 5x number from metrohash's claim that it is 5x faster than siphash?)
I also appreciate this line in the README: "HighwayHash is not a general purpose cryptographic hash function (such as Blake2b, SHA-3 or SHA-2) and should not be used if strong collision resistance is required"
I am curious to know what the threshold for "strong collision resistance" is.
For hash tables you should not rely on the false security claims of these slow hashes anyway, rather implement proper collisions strategies to get rid of O(n) attacks.
And also we've done some predictions for collisions, see: https://github.com/fwessels/HashCompare/issues/1#issuecommen...