Provided by: nvme-cli_1.5-1ubuntu1.2_amd64 
NAME
nvme-wdc-smart-add-log - Send NVMe WDC smart-add-log Vendor Unique Command, return result
SYNOPSIS
nvme wdc smart-add-log <device> [--interval=<NUM>, -i <NUM>] [--output-format=<normal|json> -o <normal|json>]
DESCRIPTION
For the NVMe device given, send a Vendor Unique WDC smart-add-log command and provide the
additional smart log. The --interval option will return performance statistics from the
specified reporting interval.
The <device> parameter is mandatory and may be either the NVMe character device (ex:
/dev/nvme0).
This will only work on WDC devices supporting this feature. Results for any other device
are undefined.
On success it returns 0, error code otherwise.
OPTIONS
-i <NUM>, --interval=<NUM>
Return the statistics from specific interval, defaults to 14
-o <format>, --output-format=<format>
Set the reporting format to human, or json. Only one output format can be used at a
time. Default is human.
Valid Interval values and description :-
┌──────┬─────────────────────────────────┐
│Value │ Description │
├──────┼─────────────────────────────────┤
│ │ │
│1 │ Most recent five (5) minute │
│ │ accumulated set. │
├──────┼─────────────────────────────────┤
│ │ │
│2-12 │ Previous five (5) minute │
│ │ accumulated sets. │
├──────┼─────────────────────────────────┤
│ │ │
│13 │ The accumulated total of sets 1 │
│ │ through 12 that contain the │
│ │ previous hour of accumulated │
│ │ statistics. │
├──────┼─────────────────────────────────┤
│ │ │
│14 │ The statistical set accumulated │
│ │ since power-up. │
├──────┼─────────────────────────────────┤
│ │ │
│15 │ The statistical set accumulated │
│ │ during the entire lifetime of │
│ │ the device. │
└──────┴─────────────────────────────────┘
CA LOG PAGE DATA OUTPUT EXPLANATION
┌────────────────────────────────┬──────────────────────────────────┐
│Field │ Description │
├────────────────────────────────┼──────────────────────────────────┤
│ │ │
│Physical NAND bytes written. │ The number of bytes written to │
│ │ NAND. 16 bytes - hi/lo │
├────────────────────────────────┼──────────────────────────────────┤
│ │ │
│Physical NAND bytes read │ The number of bytes read from │
│ │ NAND. 16 bytes - hi/lo │
├────────────────────────────────┼──────────────────────────────────┤
│ │ │
│Bad NAND Block Count │ Raw and normalized count of the │
│ │ number of NAND blocks that have │
│ │ been retired after the drives │
│ │ manufacturing tests (i.e. grown │
│ │ back blocks). 2 bytes │
│ │ normalized, 6 bytes raw count │
├────────────────────────────────┼──────────────────────────────────┤
│ │ │
│Uncorrectable Read Error Count │ Total count of NAND reads that │
│ │ were not correctable by read │
│ │ retries, all levels of ECC, or │
│ │ XOR (as applicable). 8 bytes │
├────────────────────────────────┼──────────────────────────────────┤
│ │ │
│Soft ECC Error Count │ Total count of NAND reads that │
│ │ were not correctable by read │
│ │ retries, or first-level ECC. 8 │
│ │ bytes │
├────────────────────────────────┼──────────────────────────────────┤
│ │ │
│SSD End to End Detection Count │ A count of the detected errors │
│ │ by the SSD end to end error │
│ │ correction which includes DRAM, │
│ │ SRAM, or other storage element │
│ │ ECC/CRC protection mechanism │
│ │ (not NAND ECC). 4 bytes │
├────────────────────────────────┼──────────────────────────────────┤
│ │ │
│SSD End to End Correction Count │ A count of the corrected errors │
│ │ by the SSD end to end error │
│ │ correction which includes DRAM, │
│ │ SRAM, or other storage element │
│ │ ECC/CRC protection mechanism │
│ │ (not NAND ECC). 4 bytes │
├────────────────────────────────┼──────────────────────────────────┤
│ │ │
│System Data % Used │ A normalized cumulative count of │
│ │ the number of erase cycles per │
│ │ block since leaving the factory │
│ │ for the system (FW and metadata) │
│ │ area. Starts at 0 and │
│ │ increments. 100 indicates that │
│ │ the estimated endurance has been │
│ │ consumed. │
├────────────────────────────────┼──────────────────────────────────┤
│ │ │
│User Data Max Erase Count │ The maximum erase count across │
│ │ all NAND blocks in the drive. 4 │
│ │ bytes │
├────────────────────────────────┼──────────────────────────────────┤
│ │ │
│User Data Min Erase Count │ The minimum erase count across │
│ │ all NAND blocks in the drive. 4 │
│ │ bytes │
├────────────────────────────────┼──────────────────────────────────┤
│ │ │
│Refresh Count │ A count of the number of blocks │
│ │ that have been re-allocated due │
│ │ to background operations only. 8 │
│ │ bytes │
├────────────────────────────────┼──────────────────────────────────┤
│ │ │
│Program Fail Count │ Raw and normalized count of │
│ │ total program failures. │
│ │ Normalized count starts at 100 │
│ │ and shows the percent of │
│ │ remaining allowable failures. 2 │
│ │ bytes normalized, 6 bytes raw │
│ │ count │
├────────────────────────────────┼──────────────────────────────────┤
│ │ │
│User Data Erase Fail Count │ Raw and normalized count of │
│ │ total erase failures in the user │
│ │ area. Normalized count starts at │
│ │ 100 and shows the percent of │
│ │ remaining allowable failures. 2 │
│ │ bytes normalized, 6 bytes raw │
│ │ count │
├────────────────────────────────┼──────────────────────────────────┤
│ │ │
│System Area Erase Fail Count │ Raw and normalized count of │
│ │ total erase failures in the │
│ │ system area. Normalized count │
│ │ starts at 100 and shows the │
│ │ percent of remaining allowable │
│ │ failures. 2 bytes normalized, 6 │
│ │ bytes raw count │
├────────────────────────────────┼──────────────────────────────────┤
│ │ │
│Thermal Throttling Status │ The current status of thermal │
│ │ throttling (enabled or │
│ │ disabled). 2 bytes │
├────────────────────────────────┼──────────────────────────────────┤
│ │ │
│Thermal Throttling Count │ A count of the number of thermal │
│ │ throttling events. 2 bytes │
├────────────────────────────────┼──────────────────────────────────┤
│ │ │
│PCIe Correctable Error Count │ Summation counter of all PCIe │
│ │ correctable errors (Bad TLP, Bad │
│ │ DLLP, Receiver error, Replay │
│ │ timeouts, Replay rollovers). 8 │
│ │ bytes │
└────────────────────────────────┴──────────────────────────────────┘
C1 LOG PAGE DATA OUTPUT EXPLANATION
┌───────────────────────────────┬──────────────────────────────────┐
│Field │ Description │
├───────────────────────────────┼──────────────────────────────────┤
│ │ │
│Host Read Commands │ Number of host read commands │
│ │ received during the reporting │
│ │ period. │
├───────────────────────────────┼──────────────────────────────────┤
│ │ │
│Host Read Blocks │ Number of 512-byte blocks │
│ │ requested during the reporting │
│ │ period. │
├───────────────────────────────┼──────────────────────────────────┤
│ │ │
│Average Read Size │ Average Read size is calculated │
│ │ using (Host Read Blocks/Host │
│ │ Read Commands). │
├───────────────────────────────┼──────────────────────────────────┤
│ │ │
│Host Read Cache Hit Commands │ Number of host read commands │
│ │ that serviced entirely from the │
│ │ on-board read cache during the │
│ │ reporting period. No access to │
│ │ the NAND flash memory was │
│ │ required. This count is only │
│ │ updated if the entire command │
│ │ was serviced from the cache │
│ │ memory. │
├───────────────────────────────┼──────────────────────────────────┤
│ │ │
│Host Read Cache Hit Percentage │ Percentage of host read commands │
│ │ satisfied from the cache. │
├───────────────────────────────┼──────────────────────────────────┤
│ │ │
│Host Read Cache Hit Blocks │ Number of 512-byte blocks of │
│ │ data that have been returned for │
│ │ Host Read Cache Hit Commands │
│ │ during the reporting period. │
│ │ This count is only updated with │
│ │ the blocks returned for host │
│ │ read commands that were serviced │
│ │ entirely from cache memory. │
├───────────────────────────────┼──────────────────────────────────┤
│ │ │
│Average Read Cache Hit Size │ Average size of read commands │
│ │ satisfied from the cache. │
├───────────────────────────────┼──────────────────────────────────┤
│ │ │
│Host Read Commands Stalled │ Number of host read commands │
│ │ that were stalled due to a lack │
│ │ of resources within the SSD │
│ │ during the reporting period │
│ │ (NAND flash command queue full, │
│ │ low cache page count, cache page │
│ │ contention, etc.). Commands are │
│ │ not considered stalled if the │
│ │ only reason for the delay was │
│ │ waiting for the data to be │
│ │ physically read from the NAND │
│ │ flash. It is normal to expect │
│ │ this count to equal zero on │
│ │ heavily utilized systems. │
├───────────────────────────────┼──────────────────────────────────┤
│ │ │
│Host Read Commands Stalled │ Percentage of read commands that │
│Percentage │ were stalled. If the figure is │
│ │ consistently high, then │
│ │ consideration should be given to │
│ │ spreading the data across │
│ │ multiple SSDs. │
├───────────────────────────────┼──────────────────────────────────┤
│ │ │
│Host Write Commands │ Number of host write commands │
│ │ received during the reporting │
│ │ period. │
├───────────────────────────────┼──────────────────────────────────┤
│ │ │
│Host Write Blocks │ Number of 512-byte blocks │
│ │ written during the reporting │
│ │ period. │
├───────────────────────────────┼──────────────────────────────────┤
│ │ │
│Average Write Size │ Average Write size calculated │
│ │ using (Host Write Blocks/Host │
│ │ Write Commands). │
├───────────────────────────────┼──────────────────────────────────┤
│ │ │
│Host Write Odd Start Commands │ Number of host write commands │
│ │ that started on a non-aligned │
│ │ boundary during the reporting │
│ │ period. The size of the boundary │
│ │ alignment is normally 4K; │
│ │ therefore this returns the │
│ │ number of commands that started │
│ │ on a non-4K aligned boundary. │
│ │ The SSD requires slightly more │
│ │ time to process non-aligned │
│ │ write commands than it does to │
│ │ process aligned write commands. │
├───────────────────────────────┼──────────────────────────────────┤
│ │ │
│Host Write Odd Start Commands │ Percentage of host write │
│Percentage │ commands that started on a │
│ │ non-aligned boundary. If this │
│ │ figure is equal to or near 100%, │
│ │ and the NAND Read Before Write │
│ │ value is also high, then the │
│ │ user should investigate the │
│ │ possibility of offsetting the │
│ │ file system. For Microsoft │
│ │ Windows systems, the user can │
│ │ use Diskpart. For Unix-based │
│ │ operating systems, there is │
│ │ normally a method whereby file │
│ │ system partitions can be placed │
│ │ where required. │
├───────────────────────────────┼──────────────────────────────────┤
│ │ │
│Host Write Odd End Commands │ Number of host write commands │
│ │ that ended on a non-aligned │
│ │ boundary during the reporting │
│ │ period. The size of the boundary │
│ │ alignment is normally 4K; │
│ │ therefore this returns the │
│ │ number of commands that ended on │
│ │ a non-4K aligned boundary. │
├───────────────────────────────┼──────────────────────────────────┤
│ │ │
│Host Write Odd End Commands │ Percentage of host write │
│Percentage │ commands that ended on a │
│ │ non-aligned boundary. │
├───────────────────────────────┼──────────────────────────────────┤
│ │ │
│Host Write Commands Stalled │ Number of host write commands │
│ │ that were stalled due to a lack │
│ │ of resources within the SSD │
│ │ during the reporting period. The │
│ │ most likely cause is that the │
│ │ write data was being received │
│ │ faster than it could be saved to │
│ │ the NAND flash memory. If there │
│ │ was a large volume of read │
│ │ commands being processed │
│ │ simultaneously, then other │
│ │ causes might include the NAND │
│ │ flash command queue being full, │
│ │ low cache page count, or cache │
│ │ page contention, etc. It is │
│ │ normal to expect this count to │
│ │ be non-zero on heavily utilized │
│ │ systems. │
├───────────────────────────────┼──────────────────────────────────┤
│ │ │
│Host Write Commands Stalled │ Percentage of write commands │
│Percentage │ that were stalled. If the figure │
│ │ is consistently high, then │
│ │ consideration should be given to │
│ │ spreading the data across │
│ │ multiple SSDs. │
├───────────────────────────────┼──────────────────────────────────┤
│ │ │
│NAND Read Commands │ Number of read commands issued │
│ │ to the NAND devices during the │
│ │ reporting period. This figure │
│ │ will normally be much higher │
│ │ than the host read commands │
│ │ figure, as the data needed to │
│ │ satisfy a single host read │
│ │ command may be spread across │
│ │ several NAND flash devices. │
├───────────────────────────────┼──────────────────────────────────┤
│ │ │
│NAND Read Blocks │ Number of 512-byte blocks │
│ │ requested from NAND flash │
│ │ devices during the reporting │
│ │ period. This figure would │
│ │ normally be about the same as │
│ │ the host read blocks figure │
├───────────────────────────────┼──────────────────────────────────┤
│ │ │
│Average NAND Read Size │ Average size of NAND read │
│ │ commands. │
├───────────────────────────────┼──────────────────────────────────┤
│ │ │
│NAND Write Commands │ Number of write commands issued │
│ │ to the NAND devices during the │
│ │ reporting period. There is no │
│ │ real correlation between the │
│ │ number of host write commands │
│ │ issued and the number of NAND │
│ │ Write Commands. │
├───────────────────────────────┼──────────────────────────────────┤
│ │ │
│NAND Write Blocks │ Number of 512-byte blocks │
│ │ written to the NAND flash │
│ │ devices during the reporting │
│ │ period. This figure would │
│ │ normally be about the same as │
│ │ the host write blocks figure. │
├───────────────────────────────┼──────────────────────────────────┤
│ │ │
│Average NAND Write Size │ Average size of NAND write │
│ │ commands. This figure should │
│ │ never be greater than 128K, as │
│ │ this is the maximum size write │
│ │ that is ever issued to a NAND │
│ │ device. │
├───────────────────────────────┼──────────────────────────────────┤
│ │ │
│NAND Read Before Write │ This is the number of read │
│ │ before write operations that │
│ │ were required to process │
│ │ non-aligned host write commands │
│ │ during the reporting period. See │
│ │ Host Write Odd Start Commands │
│ │ and Host Write Odd End Commands. │
│ │ NAND Read Before Write │
│ │ operations have a detrimental │
│ │ effect on the overall │
│ │ performance of the device. │
└───────────────────────────────┴──────────────────────────────────┘
EXAMPLES
• Has the program issue WDC smart-add-log Vendor Unique Command with default interval
(14) :
# nvme wdc smart-add-log /dev/nvme0
NVME
Part of the nvme-user suite.