NDCTL-WAIT-SCRUB(1)              ndctl Manual              NDCTL-WAIT-SCRUB(1)

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

SYNOPSIS
       ndctl wait-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 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.

EXAMPLE
       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
           [
             {
               "provider":"nfit_test.1",
               "dev":"ndbus3",
               "scrub_state":"idle"
             },
             {
               "provider":"nfit_test.0",
               "dev":"ndbus2",
               "scrub_state":"idle"
             }
           ]

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

           # ndctl wait-scrub e820
           error waiting for scrub completion: Operation not supported

OPTIONS
       -v, --verbose
           Emit debug messages for the ARS wait process

COPYRIGHT
       Copyright (C) 2016 - 2022, Intel Corporation. License GPLv2: GNU GPL
       version 2  <http://gnu.org/licenses/gpl.html>.  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-start-scrub(1), ACPI
       <http://www.uefi.org/sites/default/files/resources/ACPI%206_2_A_Sept29.pdf>
       6.2 Specification Section 9.20.7.2 Address Range Scrubbing (ARS)
       Overview"

ndctl                             2024-01-12               NDCTL-WAIT-SCRUB(1)