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> Does "not looking at every byte" really matter when the strings being searched for are typically so short that you're gonna hit every cache line anyway?

You're not skipping bytes of the search string, you're skipping bytes of the file being searched.

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Of course, but you can never skip more bytes than the search string is long.

But you get to skip those few bites (potentially) very many times.

yes, but the point is that on modern CPUs checking those bytes is likely far from the bottleneck and thus skipping them saves you very little time, if any at all.

You might be surprised. Consider, counting to 2 million by 5 is significantly faster than counting by 1. Especially if you just go ahead and start some prefetching in the memory, I would expect that this can speed things up considerably.

Edit: I should say I would still think things should be benchmarked to really know...

(as mentioned by yan below) Ridiculous Fish did these sorts of benchmarks here: http://ridiculousfish.com/blog/posts/old-age-and-treachery.h...

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