Not that I have anything that uses 4096 bit rsa (or any algo) crypto, but wow, crypto performance really drops off past 2048 bits on the Niagra Crypto Providers.
sign verify sign/s verify/s
rsa 512 bits 0.0000s 0.0000s 26901.1 31513.2
rsa 1024 bits 0.0000s 0.0000s 24422.0 30911.9
rsa 2048 bits 0.0000s 0.0000s 21427.3 30250.0
rsa 4096 bits 5.5400s 0.0994s 0.2 10.1
/usr/sfw/lib/openssl speed -engine pkcs11 rsa
engine "pkcs11" set.
Doing 512 bit private rsa's for 10s: 25287 512 bit private RSA's in 0.94s
Doing 512 bit public rsa's for 10s: 47585 512 bit public RSA's in 1.51s
Doing 1024 bit private rsa's for 10s: 10013 1024 bit private RSA's in 0.41s
Doing 1024 bit public rsa's for 10s: 25966 1024 bit public RSA's in 0.84s
Doing 2048 bit private rsa's for 10s: 2357 2048 bit private RSA's in 0.11s
Doing 2048 bit public rsa's for 10s: 10285 2048 bit public RSA's in 0.34s
Doing 4096 bit private rsa's for 10s: 2 4096 bit private RSA's in 11.08s
Doing 4096 bit public rsa's for 10s: 101 4096 bit public RSA's in 10.04s
OpenSSL 0.9.7d 17 Mar 2004 (+ security patches to 2006-09-29)
built on: date not available
options:bn(64,32) md2(int) rc4(ptr,char) des(ptr,risc1,16,long) aes(partial) blowfish(ptr)
compiler: information not available
available timing options: TIMES TIMEB HZ=100 [sysconf value]
timing function used: times
sign verify sign/s verify/s
rsa 512 bits 0.0000s 0.0000s 26901.1 31513.2
rsa 1024 bits 0.0000s 0.0000s 24422.0 30911.9
rsa 2048 bits 0.0000s 0.0000s 21427.3 30250.0
rsa 4096 bits 5.5400s 0.0994s 0.2 10.1
just to compare, my intel 1.8Ghz core2duo laptop
sign verify sign/s verify/s
rsa 512 bits 0.001562s 0.000107s 640.3 9304.4
rsa 1024 bits 0.007903s 0.000341s 126.5 2931.1
rsa 2048 bits 0.046388s 0.001191s 21.6 839.9
rsa 4096 bits 0.298992s 0.004227s 3.3 236.6