NOAA has been having a problem with OOM on their OSSes causing failover. Looking at collectl output from right before the crash, it appears that all the memory is being consumed by the size-256 slab:
size-256 168M 41122M 168M 41122M 11229K 43864M 11229K 43864M 200704 0.0

Is there a way to determine what those objects are and reduce the amount of memory they are taking? The vmcore is available if necessary.