NDCTL\-START\-SCRUB

Section: ndctl Manual (1)
Updated: 10/10/2020
Page Index
 

NAME

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

SYNOPSIS

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

DESCRIPTION

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.  

EXAMPLE

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


.ft C
# ndctl start-scrub
[
  {
    "provider":"nfit_test.1",
    "dev":"ndbus3",
    "scrub_state":"active"
  },
  {
    "provider":"nfit_test.0",
    "dev":"ndbus2",
    "scrub_state":"active"
  }
]
.ft

When specifying an individual bus, or if there is only one bus in the system, the command reports whether ARS support is available.


.ft C
# ndctl start-scrub e820
error starting scrub: Operation not supported
.ft

 

OPTIONS

-v, --verbose

Emit debug messages for the ARS start process
 

COPYRIGHT

Copyright (c) 2016 - 2020, Intel Corporation. License GPLv2: GNU GPL version 2 m[blue]http://gnu.org/licenses/gpl.htmlm[]. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.  

SEE ALSO

ndctl-wait-scrub(1), m[blue]ACPI 6.2 Specification Section 9.20.7.2 Address Range Scrubbing (ARS) Overviewm[][1]  

NOTES

1.
ACPI 6.2 Specification Section 9.20.7.2 Address Range Scrubbing (ARS) Overview
http://www.uefi.org/sites/default/files/resources/ACPI%206_2_A_Sept29.pdf


 

Index

NAME
SYNOPSIS
DESCRIPTION
EXAMPLE
OPTIONS
COPYRIGHT
SEE ALSO
NOTES