architecture - Confused about data allignment -


i'm trying head around why data alignment/padding necessary. wikipedia:

"when modern computer reads or writes memory address, in word sized chunks"

yet can use x86's movb instruction move data , fro @ byte resolution. missing here? thank clarification!

word aligned memory access faster byte aligned one. makes faster transfer large blocks of data. can address single byte, word read memory , internally reduced byte. makes access slower.


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