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ndctl−wait−scrub − wait for an Address Range Scrub (ARS) operation to complete


ndctl wait−scrub [<bus-id> <bus-id2> .. <bus-idN>] [<options>]


NVDIMM Address Range Scrub is a capability provided by platform firmware that allows for the discovery of memory errors by system software. It enables system software to pre−emptively avoid accesses that could lead to uncorrectable memory error handling events, and it otherwise allows memory errors to be enumerated.
The kernel provides a POLL(2) capable sysfs file (scrub) to indicate the state of ARS. The scrub file maintains a running count of ARS runs that have taken place. While a current run is in progress a + character is emitted along with the current count. The ndctl wait−scrub operation waits for scrub, across all specified buses, to indicate not in−progress at least once.


Wait for scrub on all nvdimm buses in the system. The json listing report at the end only includes the buses that support ARS operations.
# ndctl wait-scrub
When specifying an individual bus, or if there is only one bus in the system, the command reports whether ARS support is available.
# ndctl start−scrub e820
error starting scrub: Operation not supported


−v, −−verbose
Emit debug messages for the ARS wait process
Copyright (c) 2016 − 2019, Intel Corporation. License GPLv2: GNU GPL version 2 This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.


ndctl−start−scrub(1), ACPI 6.2 Specification Section Address Range Scrubbing (ARS) Overview"