Sandisk SATA SSD Plus 240GB Smart values

Internal SSD SSD Plus
1

I bought a Sandisk SATA SSD Plus 240GB as a mirror for my Debian boot drive - I ordered it on 16 October, installed it on 20 October and it has been powered up almost continuously since then. I just ran a short test and here is the smartctl -aoutput:

smartctl 7.4 2023-08-01 r5530 [x86_64-linux-6.12.15-production+truenas] (local build)
Copyright (C) 2002-23, Bruce Allen, Christian Franke, www.smartmontools.org

=== START OF INFORMATION SECTION ===
Model Family:     Marvell based SanDisk SSDs
Device Model:     SanDisk SSD PLUS 240GB
Serial Number:    25243H804812
LU WWN Device Id: 5 001b44 8c8e7da6d
Firmware Version: 42077100
User Capacity:    240,057,409,536 bytes [240 GB]
Sector Size:      512 bytes logical/physical
Rotation Rate:    Solid State Device
Form Factor:      2.5 inches
TRIM Command:     Available, deterministic
Device is:        In smartctl database 7.3/5894
ATA Version is:   ACS-4, ACS-2 T13/2015-D revision 3
SATA Version is:  SATA 3.2, 6.0 Gb/s (current: 6.0 Gb/s)
Local Time is:    Fri Nov  7 22:59:32 2025 WET
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:  (0x00) Offline data collection activity
                                        was never started.
                                        Auto Offline Data Collection: Disabled.
Self-test execution status:      ( 246) Self-test routine in progress...
                                        60% of test remaining.
Total time to complete Offline 
data collection:                (    0) seconds.
Offline data collection
capabilities:                    (0x71) SMART execute Offline immediate.
                                        No Auto Offline data collection support.
                                        Suspend Offline collection upon new
                                        command.
                                        No Offline surface scan supported.
                                        Self-test supported.
                                        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:        (  10) minutes.
Conveyance self-test routine
recommended polling time:        (   1) minutes.

SMART Attributes Data Structure revision number: 0
Vendor Specific SMART Attributes with Thresholds:
ID# ATTRIBUTE_NAME          FLAG     VALUE WORST THRESH TYPE      UPDATED  WHEN_FAILED RAW_VALUE
  5 Reallocated_Sector_Ct   0x0032   100   100   010    Old_age   Always       -       0
  9 Power_On_Hours          0x0032   100   100   000    Old_age   Always       -       21
 12 Power_Cycle_Count       0x0032   100   100   000    Old_age   Always       -       8
165 Total_Write/Erase_Count 0x0032   100   100   000    Old_age   Always       -       8590852108
166 Min_W/E_Cycle           0x0032   100   100   000    Old_age   Always       -       0
167 Min_Bad_Block/Die       0x0032   100   100   000    Old_age   Always       -       15
168 Maximum_Erase_Cycle     0x0032   100   100   000    Old_age   Always       -       1
169 Total_Bad_Block         0x0032   100   100   000    Old_age   Always       -       53
170 Unknown_Marvell_Attr    0x0032   100   100   000    Old_age   Always       -       0
171 Program_Fail_Count      0x0032   100   100   000    Old_age   Always       -       0
172 Erase_Fail_Count        0x0032   100   100   000    Old_age   Always       -       0
173 Avg_Write/Erase_Count   0x0032   100   100   005    Old_age   Always       -       0
174 Unexpect_Power_Loss_Ct  0x0032   100   100   000    Old_age   Always       -       0
184 End-to-End_Error        0x0032   100   100   097    Old_age   Always       -       0
187 Reported_Uncorrect      0x0032   100   100   000    Old_age   Always       -       0
188 Command_Timeout         0x0032   100   100   000    Old_age   Always       -       0
194 Temperature_Celsius     0x0022   100   100   014    Old_age   Always       -       31 (Min/Max 23/39)
199 SATA_CRC_Error          0x0032   100   100   000    Old_age   Always       -       0
230 Perc_Write/Erase_Count  0x0032   100   100   000    Old_age   Always       -       1 0 1
232 Perc_Avail_Resrvd_Space 0x0033   100   100   004    Pre-fail  Always       -       100
233 Total_NAND_Writes_GiB   0x0032   100   100   000    Old_age   Always       -       50
234 Perc_Write/Erase_Ct_BC  0x0032   100   100   000    Old_age   Always       -       77
241 Total_Writes_GiB        0x0030   253   253   000    Old_age   Offline      -       53
242 Total_Reads_GiB         0x0030   253   253   000    Old_age   Offline      -       23
244 Thermal_Throttle        0x0032   100   100   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  Short offline       Completed without error       00%        21         -

This drive has been running for about 2 weeks now and NOT 21 hours.

What could be happening here?

2

SMART is reporting a Power Cycle Count of 8. Perhaps your drive is going to sleep, and perhaps sleep time isn’t counted as power-on time?

3

No - that is probably correct - since I have been tweaking the hardware a few times.

4

Hey! Your SSD is fine, no errors or bad sectors. The “21 hours” showing in SMART is just how this SanDisk drive counts active usage, not actual powered-on time. It’s normal and nothing to worry about. Just keep using it and monitor for any real errors.

5

Which bit about power-on-hours in the SMART attribute standards is so difficult for Sandisk to understand?

I have software on my system to measure and monitor my disk usage and reliability, and I am expecting Sandisk to have firmware that is professional and reliable enough to actually measure the hours it is powered on. My worry, is that if they cannot get something as simple as counting hours correct, how much can I rely on any of the other SMART data that this drive provides?

My data is valuable to me. I want to be able to trust the devices and the manufacturers of those devices that I store my valuable data on.

So, I disagree completely about there being nothing to worry about.

Furthermore, Sandisk’s technical support response makes this substantially worse:

  1. They said that the drive was NOT SUPPORTED on Linux systems and only Windows despite this not being mentioned in either advertising or the product specifications;
  2. They never gave any explanation as to why this was wrong or whether it was “normal” or exceptional;
  3. They disregarded the SMART data I sent them, and refused to consider it;
  4. They told me to put the drive in a Windows machine and use their software to check the SMART data and the firmware level - and when I did the SMART data was the same and the firmware was up to date (as expected on a drive that was only 2 weeks old);
  5. I have no idea why Sandisk support couldn’t confirm that the firmware level I told them was up to date and made me jump through hoops. I can only assume that they consider their role to be avoiding RMAs rather than fixing issues or helping customers.
  6. They eventually agreed that the data was indeed incorrect;
  7. They advised me to return the product as defective to the retailer I bought it from for a full refund, and the courier has literally just collected it for return and refund.

As a consequence, I will:

  • Never trust Sandisk SSD devices with my data
  • Never purchase another Sandisk SSD
  • Recommend to others to avoid Sandisk SSDs too.

But if John Jacobb cares so little for his data that he is willing to store it on disks with functionally defective firmware that is entirely his choice.

SSD u 100 128GB problem , can not read the"power on hours count "correctly .