Messages in this thread | | | Subject | Re: [RFC] Documentation about unaligned memory access | From | Johannes Berg <> | Date | Mon, 26 Nov 2007 15:47:06 +0100 |
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> Sidenote: in the above example, you may wish to reorder the fields in the > above structure so that the overall structure uses less memory. For example, > moving field3 to sit inbetween field1 and field2 (where the padding is > inserted) would shrink the overall structure by 1 byte: > > struct foo { > u16 field1; > u8 field3; > u32 field2; > };
You can reorder to u32, u16, u8 order and save another byte :)
A reference to pahole could be appropriate here, and probably a small note that some large existing structures like netdev have deliberate holes to achieve cache alignment.
johannes [unhandled content-type:application/pgp-signature]
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