Comment 13 for bug 1638537

ssh-keygen is about 5.5 times faster than that genkey.go program on my laptop too (it's just that the times are much smaller, obviously). AIUI, generating an RSA key ends up benchmarking montgomery multiplication, and I know there are SIMD tricks you can use for that. Go doesn't seem to be using anything in this area but it looks like ssh-keygen is using openssh's routines for this and I bet they are optimized nearly as much as is possible. So, shelling out to ssh-keygen to make a key is probably going to be much faster until someone goes to the effort of improving Go's implementation...