NVME_HEALTH_INFO_LOG structure (nvme.h)
Contains fields that specify the information contained in the SMART / Health Information Log page.
The SMART / Health Information Log page provides SMART and general health information over the life of the controller that is retained across power cycles. The log page is supported on a global basis. To request the global log page, specify the namespace FFFFFFFFh.
The SMART / Health Information Log page may also be supported on a per namespace basis, as indicated in the Identify Controller data structure. If the log page is not supported on a per namespace basis, specifying any namespace other than FFFFFFFFh should abort the command with a status of NVME_STATUS_INVALID_FIELD_IN_COMMAND. In NVMe version 1.3, there is no namespace specific information defined in the SMART / Health log page, thus the global log page and namespaces specific log page contain identical information.
Critical warnings regarding the health of the NVM subsystem are indicated via an asynchronous event notification to the host. The warnings that results in an asynchronous event notification to the host are configured using the Set Features command.
Performance may be calculated using parameters returned as part of the SMART / Health Information log. Specifically, the number of Read or Write commands, the amount of data read or written, and the amount of controller busy time enables both I/Os per second and bandwidth to be calculated.
The NVME_HEALTH_INFO_LOG structure is returned by the Get Log Page command. For more information, see NVME_CDW10_GET_LOG_PAGE.
Syntax
typedef struct {
union {
struct {
UCHAR AvailableSpaceLow : 1;
UCHAR TemperatureThreshold : 1;
UCHAR ReliabilityDegraded : 1;
UCHAR ReadOnly : 1;
UCHAR VolatileMemoryBackupDeviceFailed : 1;
UCHAR Reserved : 3;
} DUMMYSTRUCTNAME;
UCHAR AsUchar;
} CriticalWarning;
UCHAR Temperature[2];
UCHAR AvailableSpare;
UCHAR AvailableSpareThreshold;
UCHAR PercentageUsed;
UCHAR Reserved0[26];
UCHAR DataUnitRead[16];
UCHAR DataUnitWritten[16];
UCHAR HostReadCommands[16];
UCHAR HostWrittenCommands[16];
UCHAR ControllerBusyTime[16];
UCHAR PowerCycle[16];
UCHAR PowerOnHours[16];
UCHAR UnsafeShutdowns[16];
UCHAR MediaErrors[16];
UCHAR ErrorInfoLogEntryCount[16];
ULONG WarningCompositeTemperatureTime;
ULONG CriticalCompositeTemperatureTime;
USHORT TemperatureSensor1;
USHORT TemperatureSensor2;
USHORT TemperatureSensor3;
USHORT TemperatureSensor4;
USHORT TemperatureSensor5;
USHORT TemperatureSensor6;
USHORT TemperatureSensor7;
USHORT TemperatureSensor8;
UCHAR Reserved1[296];
} NVME_HEALTH_INFO_LOG, *PNVME_HEALTH_INFO_LOG;
Members
CriticalWarning
A Critical Warning (CriticalWarning) structure containing fields that indicate critical warnings for the state of the controller.
Each field of the CriticalWarning structure is a bit that corresponds to a critical warning type; multiple bits may be set. If a bit is cleared to 0, then that critical warning does not apply. Bits in this field represent the current associated state and are not persistent.
Critical warnings may result in an asynchronous event notification to the host.
CriticalWarning.DUMMYSTRUCTNAME
CriticalWarning.DUMMYSTRUCTNAME.AvailableSpaceLow
Indicates whether the available spare space has fallen below the threshold.
When this value is set to 1, the available spare space has fallen below the threshold.
CriticalWarning.DUMMYSTRUCTNAME.TemperatureThreshold
Indicates whether a temperature is above an over temperature threshold or below an under temperature threshold.
When this value is set to 1, a temperature is above an over temperature threshold or below an under temperature threshold. For more information about temperature thresholds, see NVME_CDW11_FEATURE_TEMPERATURE_THRESHOLD.
CriticalWarning.DUMMYSTRUCTNAME.ReliabilityDegraded
Indicates whether the NVM subsystem reliability has been degraded.
When this value is set to 1, the NVM subsystem reliability has been degraded due to significant media related errors or any internal error that degrades NVM subsystem reliability.
CriticalWarning.DUMMYSTRUCTNAME.ReadOnly
Indicates whether the media has been placed in read only mode.
When this value is set to 1, then the media has been placed in read only mode.
CriticalWarning.DUMMYSTRUCTNAME.VolatileMemoryBackupDeviceFailed
Indicates whether the volatile memory backup device has failed.
When this value is set to 1, then the volatile memory backup device has failed. This field is only valid if the controller has a volatile memory backup solution.
CriticalWarning.DUMMYSTRUCTNAME.Reserved
Bits 05:07 of the CriticalWarning structure are reserved.
CriticalWarning.AsUchar
Temperature[2]
Indicates the composite temperature, in degrees Kelvin, of the overall device, including the controller and the NVM subsystem.
If the temperature in this field exceeds the temperature threshold, an asynchronous event completion may occur. For more information, see NVME_CDW11_FEATURE_TEMPERATURE_THRESHOLD.
Warning and critical overheating composite temperature threshold values are reported by the WCTEMP and CCTEMP fields in the Identify Controller data structure.
AvailableSpare
Indicates a normalized percentage (0 to 100) of the remaining spare capacity available.
AvailableSpareThreshold
Indicates the threshold of available spare capacity.
When the value of AvailableSpare falls below the threshold indicated in this field, an asynchronous event completion may occur. The value is indicated as a normalized percentage (0 to 100).
PercentageUsed
Indicates a vendor specific estimate of the percentage of NVM subsystem life used, based on the actual usage and the manufacturer’s prediction of NVM life.
A value of 100 indicates that the estimated endurance of the NVM in the NVM subsystem has been consumed, but may not indicate an NVM subsystem failure. The value is allowed to exceed 100. Percentages greater than 254 are represented as 255. This value is updated once per power-on hour (when the controller is not in a sleep state).
Reserved0[26]
A reserved field.
DataUnitRead[16]
Indicates the number of 512 byte data units the host has read from the controller, not including metadata.
The value of this field is reported in thousands and is rounded up. For example, a value of 1 corresponds to 1000 units of 512 bytes read. When the Logical Block Access (LBA) size is a value other than 512 bytes, the controller converts the amount of data read to 512 byte units.
For the NVM command set, logical blocks read as part of Compare and Read operations are included in this value.
DataUnitWritten[16]
Indicates the number of 512 byte data units the host has written to the controller, not including metadata.
The value of this field is reported in thousands and is rounded up. For example, a value of 1 corresponds to 1000 units of 512 bytes read. When the Logical Block Access (LBA) size is a value other than 512 bytes, the controller converts the amount of data written to 512 byte units.
For the NVM command set, logical blocks written as part of Write operations are included in this value. Write Uncorrectable commands do not impact this value.
HostReadCommands[16]
Indicates the number of Read commands completed by the controller.
For the NVM command set, this is the number of Compare and Read commands.
HostWrittenCommands[16]
Indicates the number of Write commands completed by the controller.
For the NVM command set, this is the number of Write commands.
ControllerBusyTime[16]
Indicates the amount of time, in minutes, that the controller is busy with I/O commands.
The controller is busy when there is a command outstanding to an I/O Queue. Specifically, when a command was issued via an I/O Submission Queue Tail doorbell write and the corresponding completion queue entry has not been posted yet to the associated I/O Completion Queue.
PowerCycle[16]
Indicates the number of power cycles.
PowerOnHours[16]
Indicates the number of power-on hours. This does not include time that the controller was powered and in a low power state condition.
UnsafeShutdowns[16]
Indicates the number of unsafe shutdowns. This count is incremented when a shutdown notification, indicated in the SHN filed of Controller Configuration, is not received prior to loss of power.
MediaErrors[16]
Indicates the number of occurrences where the controller detected an unrecovered data integrity error.
Media Errors such as uncorrectable ECC, CRC checksum failure, or LBA tag mismatch are included in this field.
ErrorInfoLogEntryCount[16]
Indicates the number of Error Information log entries over the life of the controller.
WarningCompositeTemperatureTime
Indicates the amount of time, in minutes, that the controller is operational and the Composite Temperature (Temperature) is greater than or equal to the Warning Composite Temperature Threshold (WCTEMP) field and less than the Critical Composite Temperature Threshold (CCTEMP) field in the Identify Controller data structure.
If the value of the WCTEMP or CCTEMP field is 0h, then this field is always cleared to 0h regardless of the Temperature value.
CriticalCompositeTemperatureTime
Indicates the amount of time in minutes that the controller is operational and the Composite Temperature (Temperature) is greater the Critical Composite Temperature Threshold (CCTEMP) field in the Identify Controller data structure.
If the value of the CCTEMP field is 0h, then this field is always cleared to 0h regardless of the Temperature value.
TemperatureSensor1
Indicates the current temperature in degrees Kelvin reported by temperature sensor 1.
TemperatureSensor2
Indicates the current temperature in degrees Kelvin reported by temperature sensor 2.
TemperatureSensor3
Indicates the current temperature in degrees Kelvin reported by temperature sensor 3.
TemperatureSensor4
Indicates the current temperature in degrees Kelvin reported by temperature sensor 4.
TemperatureSensor5
Indicates the current temperature in degrees Kelvin reported by temperature sensor 5.
TemperatureSensor6
Indicates the current temperature in degrees Kelvin reported by temperature sensor 6.
TemperatureSensor7
Indicates the current temperature in degrees Kelvin reported by temperature sensor 7.
TemperatureSensor8
Indicates the current temperature in degrees Kelvin reported by temperature sensor 8.
Reserved1[296]
A reserved field.
Remarks
The temperature reported by a temperature sensor may be used to trigger an asynchronous event. For more information, see NVME_CDW11_FEATURE_TEMPERATURE_THRESHOLD.
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client | Windows 10 |
| Header | nvme.h |