[ltta]

Modern architectures really necessitate a good understanding of the instruction pipeline and caches to squeeze out the best performance.

If I remember correctly, Python's hashtables are initialized with 8 buckets that are linearly searched and then switched to a real hashtable implementation when grown past that size.

I have worked with the L4 microkernel where sooo much emphasis was put on keeping instruction and data footprints as small as possible every time the kernel is entered in order not to dirty i- and d-caches.

And I have also seen game engine developers do amazing things in this regard. An interesting development in the gaming space is data-oriented-design that deviates from OOP among other things for performance and parallelization. See http://www.slideshare.net/mobile/cellperformance/data-orient... (though I don't agree with the three "lies" mentionened, I do like the data-centric approach).