Thanks for taking the time to read this.  We're operating on a low spec system that can not be modified at this point.  stunnel was introduced at the last minute, without consideration to resource requirements and now consumes enough ram to cause the kernel to issue OOM exceptions. 

So in short, we are trying to trade increased CPU usage for less memory usage and have tried setting “sessions” to 3600 to reduce memory pressure, but unfortunately it doesn't last.

Our current solution is to cron a restart of stunnel on a regular basis, but would prefer to limit number of threads or number of cache entries or something else altogether similarly gentler.

Thanks again for your consideration and assistance in this!  If there's any specific information I can give, please let me know.

Regards,

Jeremy