Fastest way to check if a byte array is all zeros

Question

I have a byte[4096] and was wondering what the fastest way is to check if all values are zero?

Is there any way faster than doing:

byte[] b          


        

Answer 1

I think that theoretically your way in the fastest way, in practice you might be able to make use of larger comparisons as suggested by one of the commenters (1 byte comparison takes 1 instruction, but so does an 8-byte comparison on a 64-bit system).

Also in languages closer to the hardware (C and variants) you can make use of something called vectorization where you could perform a number of the comparisons/additions simultaneously. It looks like Java still doesn't have native support for it but based on this answer you might be able to get some use of it.

Also in line with the other comments I would say that with a 4k buffer it's probably not worth the time to try and optimize it (unless it is being called very often)