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 count of this specific error type accumulated during the most recently completed 1-day collection window for this compute node, which is what lets an admin tell whether the fault is a one-off blip or actively recurring at that timescale. For example, a jump from 0 to 2 in this 1-day window would point to something like e.g. a mezzanine card or riser losing electrical contact (a loose card or failed slot) instead of an operator-initiated, orderly card removal happening twice during that period specifically, rather than a single lingering old error.