Hi Don,
A somewhat late thanks for your input.
cs have also looked. I played with ram allocation for the block solver, reducing it significantly but memory usage still ramps up and still seems entirely related to the number of steps.
I just don't understand what has to be remembered from one converged substep to the next, it's as if all solutions for all substeps are remembered or there's a memory leak.
No definitive answers. Fortunately I got the answers I needed and so my pressure was off a while back. Though I continue to play.
btw. Analysis time can be significantly altered using the config option MSE_CONTACT_INTERPENETRATION_TOLERANCE