NVME-COMPARE(1)                   NVMe Manual                  NVME-COMPARE(1)

NAME
       nvme-compare - Send an NVMe Compare command, provide results

SYNOPSIS
       nvme-compare <device> [--start-block=<slba> | -s <slba>]
                               [--block-count=<nlb> | -c <nlb>]
                               [--data-size=<size> | -z <size>]
                               [--metadata-size=<metasize> | -y <metasize>]
                               [--ref-tag=<reftag> | -r <reftag>]
                               [--data=<data-file> | -d <data-file>]
                               [--metadata=<meta> | -M <meta>]
                               [--prinfo=<prinfo> | -p <prinfo>]
                               [--app-tag-mask=<appmask> | -m <appmask>]
                               [--app-tag=<apptag> | -a <apptag>]
                               [--limited-retry | -l]
                               [--force-unit-access | -f]
                               [--dir-type=<type> | -T <type>]
                               [--dir-spec=<spec> | -S <spec>]
                               [--dsm=<dsm> | -D <dsm>]
                               [--show-command | -V]
                               [--dry-run | -w]
                               [--latency | -t]
                               [--storage-tag<storage-tag> | -g <storage-tag>]
                               [--storage-tag-check | -C]
                               [--force]
                               [--output-format=<fmt> | -o <fmt>] [--verbose | -v]

DESCRIPTION
       The Compare command reads the logical blocks specified by the command
       from the medium and compares the data read to a comparison data buffer
       transferred as part of the command. If the data read from the
       controller and the comparison data buffer are equivalent with no
       miscompares, then the command completes successfully. If there is any
       miscompare, the command completes with an error of Compare Failure. If
       metadata is provided, then a comparison is also performed for the
       metadata.

OPTIONS
       -s <slba>, --start-block=<slba>
           64-bit address of the first block to access.

       -c <nlb>, --block-count=<nlb>
           Number of blocks to be accessed (zero-based).

       -z <size>, --data-size=<size>
           Size of data to be compared in bytes.

       -y <metasize>, --metadata-size=<metasize>
           Size of metadata to be transferred in bytes.

       -r <reftag>, --ref-tag=<reftag>
           Reference Tag for Protection Information

       -d <data-file>, --data=<data-file>
           Data file.

       -M <meta>, --metadata=<meta>
           Metadata file.

       -p <prinfo>, --prinfo=<prinfo>
           Protection Information and check field.

           +----+----------------------------+
           |Bit | Description                |
           +----+----------------------------+
           |3   | PRACT: Protection          |
           |    | Information Action. When   |
           |    | set to 1, PI is            |
           |    | stripped/inserted on       |
           |    | read/write when the block  |
           |    | format's metadata size is  |
           |    | 8. When set to 0, metadata |
           |    | is passes.                 |
           +----+----------------------------+
           |2:0 | PRCHK: Protection          |
           |    | Information Check:         |
           +----+----------------------------+
           |2   | Set to 1 enables checking  |
           |    | the guard tag              |
           +----+----------------------------+
           |1   | Set to 1 enables checking  |
           |    | the application tag        |
           +----+----------------------------+
           |0   | Set to 1 enables checking  |
           |    | the reference tag          |
           +----+----------------------------+

       -m <appmask>, --app-tag-mask=<appmask>
           App Tag Mask for Protection Information

       -a <apptag>, --app-tag=<apptag>
           App Tag for Protection Information

       -l, --limited-retry
           Number of limited attempts to media.

       -f, --force-unit-access
           FUA option to guarantee that data is stored to media.

       -T <type>, --dir-type=<type>
           Optional directive type. The nvme-cli only enforces the value be in
           the defined range for the directive type, though the NVMe
           specification (1.3a) defines only one directive, 01h, for write
           stream identifiers.

       -S <spec>, --dir-spec=<spec>
           Optional field for directive specifics. When used with write
           streams, this value is defined to be the write stream identifier.
           The nvme-cli will not validate the stream requested is within the
           controller's capabilities.

       -D <dsm>, --dsm=<dsm>
           The optional data set management attributes for this command. The
           argument for this is the least significant 8 bits of the DSM field
           in a write command; the most significant 16 bits of the field come
           from the directive specific field, if used. This may be used to set
           attributes for the LBAs being written, like access frequency, type,
           latency, among other things, as well as yet to be defined types.
           Please consult the NVMe specification for detailed breakdown of how
           to use this field.

       -V, --show-cmd
           Print out the command to be sent.

       -w, --dry-run
           Do not actually send the command. If want to use --dry-run option,
           --show-cmd option must be set. Otherwise --dry-run option will be
           ignored.

       -t, --latency
           Print out the latency the IOCTL took (in us).

       -g <storage-tag>, --storage-tag=<storage-tag>
           Variable Sized Expected Logical Block Storage Tag(ELBST).

       -C, --storage-tag-check
           This flag enables Storage Tag field checking as part of end-to-end
           data protection processing.

       --force
           Ignore namespace is currently busy and performed the operation even
           though.

       -o <fmt>, --output-format=<fmt>
           Set the reporting format to normal, json or binary. Only one output
           format can be used at a time.

       -v, --verbose
           Increase the information detail in the output.

EXAMPLES
       No examples yet.

NVME
       Part of the nvme-user suite

NVMe                              02/16/2024                   NVME-COMPARE(1)