Do you have measurements that show that urandom is slower than a SHA1 hash on Linux? I don't have a good sense for how fast/slow the read call is (obviously you

Do you have measurements that show that urandom is slower than a SHA1 hash on Linux? I don't have a good sense for how fast/slow the read call is (obviously you can cache the fd across reads). Also, I can't find references to OS X or any other OS blocking on urandom reads. Can you point me to one?