PJSIP Perfoemance improvements

For people who like metrics, Kevin Harwell posted a new article on the Asterisk blog.

Measuring performance in Asterisk, like most software systems for that matter, can be a complicated task. When testing performance it is important to define goals, and limit the context for that which is being tested. It’s been previously shown that res_pjsip might have an efficiency problem when it comes to inbound registration.

Our main goal for this round of testing was to check the performance in res_pjsip with regards to inbound registration. We wanted to find out how much CPU was being used, and where its time was being spent. As well, we desired to monitor memory usage. Lastly, we also wanted to compare the res_pjsip results to chan_sip to see how they stacked up. We would then be able to ascertain whether or not there was a real performance issue.