CHECK(IBMUSS,USS_KERNEL_PVTSTG_THRESHOLD) determined that the percent of allocated monitored (non-stack cell pool private storage) kernel private storage has exceeded the current check threshold.

Monitored private storage is considered all private storage below the bar that has not been allocated for stack cell pool cells. During initialization the kernel designates 80% of the region as the maximum storage that can be allocated for stack cell pool cells and the remaining 20% as the maximum private storage. If the allocated non-stack cell private storage exceeds 20% and overflows into the 80% designated for stack cells it will reduce the maximum number of stack cells that can be allocated. The percent of monitored storage allocated can exceed 100% if it exceeds the 20% designated during kernel initialization and overflows into the 80% designated for stack cells.