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by thomaslutz 3972 days ago
Why should it not be similar faster on mobile?
3 comments

No only different instruction set, but probably drastically different cache hierarchy and branch predictors. The tool cachegrind which they are using is simulating a program's effect on the cache and branch predictor, which will likely both be dramatically smaller in embedded devices vs modern server CPUs, so the results may be very misleading to real world applications for sqite.
Also multicore memory hierarchies are very different on ARM -- e.g. atomics are much more expensive there in my experience.
Different instruction set. The release notification isn't very clear about what optimizations took place. It is quite possible that it will not be the same result on a different architecture.
Even moreso, different cache sizes. Some object that might fit nicely in a 4kB cache might get destroyed with a 1kB cache.
He never said it shouldn't, just that he would be interested in seeing the numbers. I would be too since they would be more relevant to my use case.