First, on your assembly output: mine was a 64-bit system, and there's one opcode that's different. Ok, doesn't matter. Second, the fact that your timing is not

First, on your assembly output: mine was a 64-bit system, and there's one opcode that's different. Ok, doesn't matter. Second, the fact that your timing is not a lot different for sizes that fit the cache means your system probably lacks some kind of smarter instruction pipelining which is, I presume, present on mine. To be honest, I have no idea why in my case there was such a notable difference, i.e. from 12 to 45 seconds, while in your case it's 30 to 59.