handshake: add freeze option

[npajkovsky]

No description provided.

[Sashan]

I like the change.

FYI I gave it a try with openssl from Nikola's frozen branch and those the numbers:
regular run with 64 threads

Average time per handshake: 3975.056520us
Handshakes per second: 16100.400000

frozen run with 64 threads:

Average time per handshake: 2037.905034us
Handshakes per second: 31404.800000

and those are numbers with -s option which disables context sharing:

sashan@work:~/work.openssl/perftools.nikola/source/build$ ./handshake -s /home/sashan/work.openssl/openssl/test/certs 64
Average time per handshake: 7952.879191us
Handshakes per second: 8047.400000
sashan@work:~/work.openssl/perftools.nikola/source/build$ ./handshake -f -s /home/sashan/work.openssl/openssl/test/certs 64
Average time per handshake: 3232.257934us
Handshakes per second: 19800.400000

[t8m]

This looks like a very nice perf improvement. What would be the numbers with just a single thread runs?

[Sashan]

This looks like a very nice perf improvement. What would be the numbers with just a single thread runs?

results for single thread:

sashan@work:~/work.openssl/perftools.nikola/source/build$ ./handshake -f /home/sashan/work.openssl/openssl/test/certs 1
Average time per handshake: 1219.512195us
Handshakes per second: 820.000000
sashan@work:~/work.openssl/perftools.nikola/source/build$ ./handshake /home/sashan/work.openssl/openssl/test/certs 1
Average time per handshake: 1216.545012us
Handshakes per second: 822.000000
sashan@work:~/work.openssl/perftools.nikola/source/build$ ./handshake -f -s /home/sashan/work.openssl/openssl/test/certs 1
Average time per handshake: 1940.240590us
Handshakes per second: 515.400000
sashan@work:~/work.openssl/perftools.nikola/source/build$ ./handshake -s /home/sashan/work.openssl/openssl/test/certs 1
Average time per handshake: 1955.416504us
Handshakes per second: 511.400000

[t8m]

Hmm... that's interesting.