On Wed, Aug 17, 2011 at 2:23 PM, Dmitry Kasatkin <dmitry.kasatkin@xxxxxxxxx> wrote: >> Was there a particular reason to select the GnuPG mpi lib? Why not >> include gmp (the gnupg mpi lib is a very old fork of gmp), or some other >> big number library? > GNUPG MPI kernel port was available and has shown the best performance > comparing to other kernel implementations > such as LibTomMath and once other rsa implementation.. > In fact I took libtommath from your cryptodev-linux#newapi project. > I have patches and RSA implementation in my git trees. > IIRC performance was about twice worse than in Gnupg MPI lib... Quite impressive [0]. In GnuTLS we had the same (2x) performance optimization by switching to gmp from the gnupg mpi. I remember some projects ported gmp to linux kernel, but I don't know how wise that would be. Gmp (and the original gnupg mpi - don't know about the port) have no easy way to indicate memory allocation failure. That was my reason to select libtommath instead of them. regards, Nikos [0]. There is a limitation in libtommath as I ported it in the linux kernel. It uses 32-bit numbers even in x86-64. Libtommath required an 128-bit type to support 64-bit numbers that was available to user-space via gcc but not in linux-kernel. Performance of mpi was not my goal then, so I didn't investigate it more. -- To unsubscribe from this list: send the line "unsubscribe linux-crypto" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
