bionic (1) nvme-wdc-smart-add-log.1.gz
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 │ Percentage of read commands that 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 commands │
│Percentage │ 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 commands │
│Percentage │ 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 that │
│Percentage │ 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.