#11 Reuse PKCS12 certs to avoid SecPKCS12Import performance hit

[na-gupta]

Description

Testing Kitura with SSLService causes a significant slowdown on osx (but not on linux). On investigating, it appears that SecPKCS12Import() (that runs every time a listening socket accepts a connection and initializes it's delegate) is very expensive. If we cache and reuse the pkcs12 certs in SSLService.Configuration we get a significant performance increase.

Testing this change with wrk shows a performance improvement from about 150 Requests/sec to about 5200 Requests/sec (35x improvement). It still is much slower than without SSL (24k Requests/sec).

On linux, using OpenSSL, the performance is comparable to without SSL. So there are probably other areas of potential improvement.

Motivation and Context

#11

How Has This Been Tested?

Using Kitura test suite

Checklist:

• I have submitted a CLA form
• If applicable, I have updated the documentation accordingly.
• If applicable, I have added tests to cover my changes.

[billabt]

The changes look good to me. However, there's a couple of places where some additional comments would be useful. After I merge this PR (once CI has completed), I'll add the additional documentation. I've been meaning to do this for a little while now but keep forgetting. Thanks for the changes.

[na-gupta]

Thanks! Most of the changes are just added indentation because of the new condition. You probably already know this, but if not, to ignore whitespace changes, add ?w=1 to the end of the github URL. Makes it a lot easier.

[billabt]

Thanks for the tip... I knew about it but am forever forgetting what to put in. 🙄 Must be getting old...