FA-72195 / Error-correcting codes / Member archive

Row retirement re-retires rows on later events · case 05

Retirement timestamps move later as more errors arrive on an already retired row.

Member previewVariant 5 · 3 implementations · 8 checks per implementation

Case contract

Memory-controller ECC policy. events are [time, row, kind] with kind "ce" (corrected) or "ue" (uncorrectable), processed in time order (stable for equal times). A "ue" retires its row immediately. A "ce" is added to the row's history, entries at or before time - window expire, and the row retires when the remaining count reaches the threshold. Events for a retired row are ignored. Return sorted [row, retirement time] pairs.

Why this case matters

Servers retire DRAM rows that show repeated corrected errors before they turn uncorrectable.

One recorded failure

Sample boundary fixture

This sample comes from the broken implementation of a controlled reproducer.

Boundary fixture	Actual	Expected	Outcome
regression [[[21, 9, "ce"], [27, 2, "ue"], [0, 2, "ue"], [21, 1, "ce"], [9, 10...	`[[2, 27]]`	`[[2, 0]]`	Failed

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