Calling std::nth_element() function extremely frequently

Question

I did not find this specific topic anywhere...

I am calling the nth_element() algorithm about 400,000 times per second on different data in a std::vector of 23 integers,

Answer 1

I found this problem interesting, so I tried all the algorithms I could think of.
Here are the results:

testing 100000 repetitions
variant 0, no-op (for overhead measure)
5 ms
variant 1, vector + nth_element
205 ms
variant 2, multiset + advance
745 ms
variant 2b, set (not fully conformant)
787 ms
variant 3, list + lower_bound
589 ms
variant 3b, list + block-allocator
269 ms
variant 4, avl-tree + insert_sorted
645 ms
variant 4b, avl-tree + prune
682 ms
variant 5, histogram
1429 ms

I think we can conclude, that you where already using the fastest algorithm. Boy was I wrong. However, if you can accept an approximate answer, there are probably faster ways, such as median of medians.
If you are interested, the source is here.