Most of the time an easy optimization is to pad fields of your struct to a 32 bit boundary. Almost any compiler will do this for you (look up "struct alignment

Most of the time an easy optimization is to pad fields of your struct to a 32 bit boundary. Almost any compiler will do this for you (look up "struct alignment / padding"). If the compiler is going to do this anyway, might as well use the memory yourself instead of letting it be empty space. If it doesn't happen, you leave performance on the table, so doing this raises the chance that your struct/fields will be aligned. Nuance is that each field should be at an address divisible by the fields size or wordline size, not some magic 32 constant. The entire struct should also be padded to a multiple of the largest fields size. In practice this usually means 32 bit alignment. Ref http://www.catb.org/esr/structure-packing/ http://www.catb.org/esr/structure-packing/