Documentation for ndctl and daxctl


ndctl-start-scrub - start an Address Range Scrub (ARS) operation


ndctl start-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 sysfs file (scrub) that when written with the string “1\n” initiates an ARS operation. The ndctl start-scrub operation starts an ARS, across all specified buses, and the kernel in turn proceeds to scrub every persistent memory address region on the specified buses.


Start a scrub on all nvdimm buses in the system. The json listing report only includes the buses that support ARS operations.

# ndctl start-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 start process


Copyright © 2016 - 2020, 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-wait-scrub , ACPI 6.2 Specification Section Address Range Scrubbing (ARS) Overview