Are there any up-to-date Prolog implementation benchmarks (with results)?

I found [this](https://www.mercurylang.org/about/bench/ratios.html) on the [mercury](/questions/tagged/mercury "show questions tagged 'mercury'") web site. Surprisingly, it shows a 20-fold gap between [swi-prolog](/questions/tagged/swi-prolog "show questions tagged 'swi-prolog'") and Aquarius. I suspect that these results are pretty old. Does this gap still hold? Personally, I'd also like to see some comparisons with the occurs check turned on, since it has a major impact on performance, and some compilers might be better than others at optimizing it away.

Of more recent comparisons, I found [this](http://www.david-reitter.com/compling/prolog/compare.html) claim that [gnu-prolog](/questions/tagged/gnu-prolog "show questions tagged 'gnu-prolog'") is 2x faster than SWI, and YAP is 4x faster than SWI on one specific code base.

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Edit:

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> a specific case where the occurs check is needed for a real world problem
> 
> 
> 

Sure: [type inference in Haskell, OCaml, Swift](https://stackoverflow.com/questions/12493773/) or theorem provers such as [this one](http://www.ai.sri.com/%7Estickel/pttp.html). I also think the burden is on the programmer to prove that his code doesn't need the occurs check. [Tests can only prove that you do need it, not that you don't need it](https://ronjeffries.com/xprog/articles/qa/xp_q_and_a_absence/).