Table 11: SMART/Health Information (Log Identifier 02h)
Bytes Name Description
0 Critical warning Indicates critical warnings for the state of the controller. Each bit corre-
sponds to a critical warning type; multiple bits may be set. If a bit is
cleared to 0, the critical warning does not apply. Critical warnings may
result in an asynchronous event notification to the host.
• Bit 00: If set to 1, the available spare space has fallen below the
• Bit 01: If set to 1, the temperature has exceeded a critical threshold.
• Bit 02: If set to 1, the device reliability has been degraded due to sig-
nificant media-related errors or any internal error that degrades de-
• Bit 03: If set to 1, the media has been placed in read-only mode.
• Bit 04: If set to 1, the volatile memory backup device has failed. This
field is only valid if the controller has a volatile memory backup solu-
• Bits 07:05: Reserved.
2:1 Temperature Contains the temperature of the overall device (controller and NVM in-
cluded) in units of Kelvin. If it exceeds the temperature threshold, an
asynchronous event may be issued to the host. For the 9100, the value
reported is the maximum temperature measured on either the board
3 Available spare Contains a normalized percentage (0–100%) of the remaining available
spare capacity, beginning at 100% and decreasing.
4 Available spare threshold When the available spare falls below the threshold indicated in this
field, an asynchronous event may be issued to the host. The value is in-
dicated as a normalized percentage (0–100%). Threshold is set to 5%.
5 Percentage used Contains a vendor-specific estimate of the percentage of the device life
used based on the actual device usage and the manufacturer's predic-
tion of device life.
A value of 100 indicates that the estimated endurance of the device
has been consumed, but may not indicate a device failure.
Refer to the JEDEC JESD218 standard for SSD device life and endurance
31:6 Reserved Reserved.
47:32 Data units read Contains the number of 512-byte data units the host has read from the
controller; this value does not include metadata. This value is reported
in thousands (that is, a value of 1 corresponds to 1000 units of 512
bytes read) and is rounded up. When the LBA size is a value other than
512 bytes, the controller shall convert the amount of data read to 512-
9100 U.2 and HHHL NVMe PCIe SSDs
9100_hhhl_u2_nvme_pcie_ssd.pdf - Rev. I 03/17 EN
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