[fpc-pascal] Memory alignment with FPC

[Jonas Maebe]

On 11 Oct 2012, at 16:11, dhkblaszyk at zeelandnet.nl wrote:

> On 11 okt '12, Jonas Maebe wrote:
>
>> No. You really should write the fields one by one. Yes,
>> it's slower. That's the cost of portability. You can always  
>> optimize by
>> first writing them to a buffer and then writing the buffer in one go.
>
> Sorry I keep asking questions, but why write them one by one? If
> I would store the offset each variable has at the time of writing  
> (only
> need to do one time per record type), I could easily make the loading
> work (even if the ABI changes when the file is read back). What makes
> you prefer writing the variables one by one over once at a time?

I always prefer simple techniques over elaborate strategies aimed at  
optimizing things, especially if it's not clear that they will ever be  
the performance bottleneck in the first place. You're moreover trading  
space (storing all the offsets) for cpu operations here, and I/O is  
generally two or more orders of a magnitude slower than moving data in  
memory.


Jonas
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