"LifeTime(hours)" wrap around in SMART's self-test log

[C_Aulbert]

Hi

I've just seen that on a few quite old disks, the 16bit counter for "LifeTime(hours)" wraps around after a few years, even though the power on hours don't.

I'm not sure if this is caused the SMART specs or a problem with querying the raw values within smartmontools, but it would be nice to have a fix in smartmontools to have a uniformly growing number of LifeTime in the logs - especially as we use the difference between the latest entry and attribute no 9 to determine if a regular check was not performed.

What do you think?

Cheers

Carsten

smartctl 6.5 2016-04-02 r4276 [x86_64-linux-3.18.26-atlas] (daily-20160402)
Copyright (C) 2002-16, Bruce Allen, Christian Franke, www.smartmontools.org

START OF INFORMATION SECTION

Model Family: Hitachi Ultrastar A7K1000
Device Model: Hitachi HUA721075KLA330
Serial Number: GTE200P8G1Z07E
LU WWN Device Id: 5 000cca 215c0e504
Firmware Version: GK8OA70M
User Capacity: 750,156,374,016 bytes [750 GB]
Sector Size: 512 bytes logical/physical
Device is: In smartctl database [for details use: -P show]
ATA Version is: ATA/ATAPI-7 T13/1532D revision 1
Local Time is: Mon Apr 4 13:07:04 2016 UTC
SMART support is: Available - device has SMART capability.
SMART support is: Enabled

START OF READ SMART DATA SECTION

SMART overall-health self-assessment test result: PASSED

General SMART Values:
Offline data collection status: (0x85) Offline data collection activity

was aborted by an interrupting command from host.
Auto Offline Data Collection: Enabled.

Self-test execution status: ( 249) Self-test routine in progress...

90% of test remaining.

Total time to complete Offline
data collection: (11471) seconds.
Offline data collection
capabilities: (0x5b) SMART execute Offline immediate.

Auto Offline data collection on/off support.
Suspend Offline collection upon new
command.
Offline surface scan supported.
Self-test supported.
No Conveyance Self-test supported.
Selective Self-test supported.

SMART capabilities: (0x0003) Saves SMART data before entering

power-saving mode.
Supports SMART auto save timer.

Error logging capability: (0x01) Error logging supported.

General Purpose Logging supported.

Short self-test routine
recommended polling time: ( 1) minutes.
Extended self-test routine
recommended polling time: ( 191) minutes.
SCT capabilities: (0x003f) SCT Status supported.

SCT Error Recovery Control supported.
SCT Feature Control supported.
SCT Data Table supported.

SMART Attributes Data Structure revision number: 16
Vendor Specific SMART Attributes with Thresholds:
ID# ATTRIBUTE_NAME FLAG VALUE WORST THRESH TYPE UPDATED WHEN_FAILED RAW_VALUE

1 Raw_Read_Error_Rate 0x000b 100 100 016 Pre-fail Always - 0
2 Throughput_Performance 0x0005 130 130 054 Pre-fail Offline - 151
3 Spin_Up_Time 0x0007 118 118 024 Pre-fail Always - 542 (Average 472)
4 Start_Stop_Count 0x0012 100 100 000 Old_age Always - 82
5 Reallocated_Sector_Ct 0x0033 100 100 005 Pre-fail Always - 2
7 Seek_Error_Rate 0x000b 100 100 067 Pre-fail Always - 0
8 Seek_Time_Performance 0x0005 132 132 020 Pre-fail Offline - 33
9 Power_On_Hours 0x0012 091 091 000 Old_age Always - 66329

10 Spin_Retry_Count 0x0013 100 100 060 Pre-fail Always - 0
12 Power_Cycle_Count 0x0032 100 100 000 Old_age Always - 82

192 Power-Off_Retract_Count 0x0032 100 100 000 Old_age Always - 868
193 Load_Cycle_Count 0x0012 100 100 000 Old_age Always - 868
194 Temperature_Celsius 0x0002 166 166 000 Old_age Always - 36 (Min/Max 8/47)
196 Reallocated_Event_Count 0x0032 100 100 000 Old_age Always - 2
197 Current_Pending_Sector 0x0022 100 100 000 Old_age Always - 0
198 Offline_Uncorrectable 0x0008 100 100 000 Old_age Offline - 0
199 UDMA_CRC_Error_Count 0x000a 200 200 000 Old_age Always - 0

SMART Error Log Version: 1
No Errors Logged

SMART Self-test log structure revision number 1
Num Test_Description Status Remaining LifeTime(hours) LBA_of_first_error
# 1 Extended offline Completed without error 00% 676 -
# 2 Extended offline Completed without error 00% 508 -
# 3 Extended offline Completed without error 00% 340 -
# 4 Extended offline Completed without error 00% 172 -
# 5 Extended offline Completed without error 00% 4 -
# 6 Extended offline Completed without error 00% 65372 -
# 7 Extended offline Completed without error 00% 65205 -
# 8 Extended offline Completed without error 00% 64868 -
# 9 Extended offline Completed without error 00% 64700 -
#10 Extended offline Completed without error 00% 64532 -
#11 Extended offline Completed without error 00% 64484 -
#12 Extended offline Completed without error 00% 12930 -
#13 Extended offline Completed without error 00% 12762 -
#14 Extended offline Completed without error 00% 12594 -
#15 Extended offline Completed without error 00% 12426 -
#16 Extended offline Completed without error 00% 12258 -
#17 Extended offline Completed without error 00% 12090 -
#18 Extended offline Completed without error 00% 11922 -
#19 Extended offline Completed without error 00% 11754 -
#20 Extended offline Completed without error 00% 11586 -
#21 Extended offline Completed without error 00% 11418 -

SMART Selective self-test log data structure revision number 1

SPAN MIN_LBA MAX_LBA CURRENT_TEST_STATUS

1 0 0 Not_testing
2 0 0 Not_testing
3 0 0 Not_testing
4 0 0 Not_testing
5 0 0 Not_testing

Selective self-test flags (0x0):

After scanning selected spans, do NOT read-scan remainder of disk.

If Selective self-test is pending on power-up, resume after 0 minute delay.