We have been using Kafka in some of our projects for the past couple of
years. Our experience with Kafka and SSL had shown some performance
issues when we had seriously tested it (which admittedly was around a
year back). Our basic tests did show that things had improved over time
with newer versions, but we didn't get a chance to fully test and move
to SSL for Kafka.
Incidentally, I happened to be looking into some other things related to
SSL and decided to experiment with using openssl as the SSL provider for
Kafka. I had heard OpenSSL performs better than the engine shipped
default in JRE, but hadn't ever got a chance to do any experiments. This
past few weeks, I decided to spend some time trying it. I have noted the
experimentation and the performance numbers in my blog[1]. The initial
basic performance testing (using the scripts shipped in Kafka) does show
promising improvements. Like I note in my blog, this was a very basic
performance test just to see if OpenSSL can be pursued as an option
(both in terms of being functional and performant) if we do decide to.
I know some of the members in these lists do extensive performance
testing with Kafka (and SSL), so I thought I will bring this to their
notice.
[1] https://jaitechwriteups.blogspot.com/2017/10/kafka-with-openssl.html
-Jaikiran