Hello Jay,
Monday, March 27, 2006, 12:25:36 PM, you wrote: JS> On 3/27/06, Alexei Alexandrov <[EMAIL PROTECTED]> wrote: >> > >> > Isn't this eliminated with the proper compile settings for data packing? >> > There should be a compile option for sometihng like 'align data on N >> > byte boundaries' >> > >> >> Even if that is possible, I don't want to say to compiler "Please >> align everything on 16 bytes" because this will lead to huge memory >> footprint overhead - every element - even 1 byte-long will take 16 >> bytes in memory. This is not an option. JS> The compiler I used was smarter than that in the 1980's... I agree. Typically it's just structure alignments so, for instance if you had a char followed by a short in the struct, it would get padded out to 16 bytes but, it wouldn't pad unless it had too. 15 chars for instance would have a 1 byte pad. Structs HAVE to be aligned in order to prevent unaligned access unless you're working with something byte centric like a net protocol which requires you to work with no or smaller alignments. The native alignment for my windows apps is 8 bytes. When I tried Visual Studio 2005, the default alignment was 16 bytes (which caused me some real problems till I figured it out). Unless the on disk format is carried over into memory, there's no reason not to use a structure alignment which prevents unaligned access. I'm a little surprised your compiler hadn't already padded the struct out to proper alignment when you built SQLite. -- Best regards, Teg mailto:[EMAIL PROTECTED]
