NVME_CONTEXT_ATTRIBUTES union (nvme.h)

Specifies optional context attributes for a logical block range (LBA range).

The context attributes specified for each LBA range provides information about how the range is intended to be used by host software. The use of this information is optional and the controller is not required to perform any specific action.

Note

The controller is required to maintain the integrity of data on the NVM media regardless of whether the attributes provided by host software are accurate.

This structure is used in the Attributes field of the NVME_LBA_RANGE structure, which is used by the Dataset Management command.

Syntax

typedef union {
  struct {
    ULONG AccessFrequency : 4;
    ULONG AccessLatency : 2;
    ULONG Reserved0 : 2;
    ULONG SequentialReadRange : 1;
    ULONG SequentialWriteRange : 1;
    ULONG WritePrepare : 1;
    ULONG Reserved1 : 13;
    ULONG CommandAccessSize : 8;
  } DUMMYSTRUCTNAME;
  ULONG  AsUlong;
} NVME_CONTEXT_ATTRIBUTES, *PNVME_CONTEXT_ATTRIBUTES;

Members

DUMMYSTRUCTNAME

DUMMYSTRUCTNAME.AccessFrequency

An NVME_ACCESS_FREQUENCIES value that indicates the access frequency of the LBA range.

DUMMYSTRUCTNAME.AccessLatency

An NVME_ACCESS_LATENCIES value that indicates the access latency of the LBA range.

DUMMYSTRUCTNAME.Reserved0

DUMMYSTRUCTNAME.SequentialReadRange

Indicates whether the dataset should be optimized for sequential read access.

When this value is set to 1, the dataset should be optimized for sequential read access. The host expects to perform operations on the dataset as a single object for reads.

DUMMYSTRUCTNAME.SequentialWriteRange

Indicates whether the dataset should be optimized for sequential write access.

When this value is set to 1, the dataset should be optimized for sequential write access. The host expects to perform operations on the dataset as a single object for writes.

DUMMYSTRUCTNAME.WritePrepare

Indicates whether the specified LBA range is expected to be written in the near future.

When this value is set to 1, the provided range is expected to be written in the near future.

DUMMYSTRUCTNAME.Reserved1

DUMMYSTRUCTNAME.CommandAccessSize

Specifies the number of logical blocks that are expected to be transferred in a single Read or Write command from this dataset.

A value of 0h indicates that no Command Access Size is provided.

AsUlong

Requirements

Requirement	Value
Minimum supported client	Windows 10
Header	nvme.h