While we were discussing TLS throughput over TCPIP I found an interesting fact - but it should make no difference!
- When using a channel without TLS, MQ cuts the messages into chunks of up to 32KB.
- When using a channel with TLS, The call to the crypto facility does it in chunks of 16KB and then MQ sends it. This means that to send 32KB of data, there are now two send requests each of 16KB.
Sending the data as two 16KB chunks instead of one 32KB chunk should make little difference, as you should be using large TCP window sizes ( eg send many chunks before the remote end sends back the TCP ACK).
It may make a difference if your network is not fine tuned, and so there is more data flowing within TCP to ACKnowledge two chunks instead of one chunk.