Usually I won't showcase an Add'On that is not mine or at least being maintained by me. But this one deserves am exception.
This test was conducted on a MacPotato, I mean, MacMini Mid 2011 (i5 2.3GHz), and the footage wasn't edited. The performance you see here is the performance i got on the MacPotato.
The video was shot using KSP 1.6.1, Infernal Robotics Next, KJR/L (my personal fork of KJR with the Rudolf Meier's code merged in, and some bells and whistles from me) and some other mods, being Kerbal Foundries, Grounded and SXT the most visible ones.
The performance I got with KJR/L is almost the same the performacne I got without, except when parts explode - I suspect that the joint list building still have some optimizations awaiting to be done. :) But it's a guess, Rudolf is the one that really knows what he was doing. :D
The KSP.LOG for further evidences can be found here.
Infernal Robotics Next can be downloaded from the Add'On's OP on Forum, and the KJR/L is available from this post, also from Forum.
This would not be running on 1.6.1 without the excellent efforts from Rudolf Meier, the real hero here. Thanks, Dude.
KSP 1.6.1 + Infernal Robotics Next + KJR/L (and a bunch of mods)
KSP 1.6.1 + Infernal Robotics Next + KJR/"Stock" (and a bunch of mods)
The KJR used is the Ferram's 3.3.3 hacked and recompiled to run on any KSP version.
KSP 1.6.1 + Infernal Robotics Next (and a bunch of mods)
Absolutely no Joint Reinforcements used - not even stock's auto-struts. But some Impossible Innovations' Iridium Struts are used