This field is part of the PCIeFatalStats table's tally of surprise-link-down errors on this compute node's PCIe fabric — this specific fault fires when a PCIe link drops to the Down state without going through the normal, orderly link-training/removal sequence. This is the running cumulative total of this error type counted since this counter object was created or last reset/wrapped — the base tally that the 15-minute/hourly/daily/weekly figures on this same compute node's PCIeFatalStats table are derived from. For example, a steadily climbing raw count (say from 12 to 15) while the current 15-minute window shows 0 tells an admin the errors (e.g. a mezzanine card or riser losing electrical contact (a loose card or failed slot) instead of an operator-initiated, orderly card removal) happened earlier in the counter's lifetime, not in the last 15 minutes.