3. We use SWIG to talk to shared memory. Does anyone have any idea the difference in performance between hand rolling XS over SWIG for reading attributes off a C Structure? (or is there some even "better" way to do this kind of thing that I've never heard of?)

SWIG wrappers are very inefficient!

The way it uses a tie interface to expose C struct attributes, and the double wrapping of objects it performs, makes it more than an order of magnitude slower than an equivalent hand-crafted XS interface (note that I am talking exclusively about the wrapping, obviously, the C functions behind, take the same time no matter if you use SWIG or XS!).

In reply to Re: Optimizing a large project. by salva
in thread Optimizing a large project. by dextius

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