[QNAP TR-002] usb reset SuperSpeed device when using -x flag

[lemonuk]

The spinning drive is connected to ​QNAP TR-002.
Using the flag -x causes the data read/write transmission to freeze temporarily while the smart test is being performed, then just keeps running normally:

# time smartctl -x -d sat /dev/sdc | grep -i temperature
194 Temperature_Celsius     -O---K   100   100   000    -    35 (Min/Max 14/52)

real    1m1.655s
user    0m0.041s
sys     0m0.004s

dmesg complains about it every time the command is run:

[ 1462.569558] usb 2-5: reset SuperSpeed USB device number 3 using xhci_hcd

Using the -a flag does not cause that issue and is much faster:

# time smartctl -a -d sat /dev/sdc | grep -i temperature
194 Temperature_Celsius     0x0022   100   100   000    Old_age   Always       -       38 (Min/Max 14/52)

real    0m0.113s
user    0m0.026s
sys     0m0.005s

Connecting the drive to ​StarTech.com SDOCKU33EF is much faster and does not raise any dmesg log even with -x flag:

# time smartctl -x -d sat /dev/sdc | grep -i temperature
194 Temperature_Celsius     -O---K   100   100   000    -    40 (Min/Max 14/52)
Current Temperature:                    40 Celsius
Power Cycle Min/Max Temperature:     35/40 Celsius
Lifetime    Min/Max Temperature:     14/52 Celsius
Specified Max Operating Temperature:    55 Celsius
Under/Over Temperature Limit Count:   0/0
SCT Temperature History Version:     2
Temperature Sampling Period:         1 minute
Temperature Logging Interval:        1 minute
Min/Max recommended Temperature:      5/55 Celsius
Min/Max Temperature Limit:           -40/70 Celsius
Temperature History Size (Index):    478 (107)
Index    Estimated Time   Temperature Celsius
0x05  =====  =               =  ===  == Temperature Statistics (rev 1) ==
0x05  0x008  1              40  ---  Current Temperature
0x05  0x010  1              36  N--  Average Short Term Temperature
0x05  0x018  1               -  N--  Average Long Term Temperature
0x05  0x020  1              52  ---  Highest Temperature
0x05  0x028  1              14  ---  Lowest Temperature
0x05  0x030  1              46  N--  Highest Average Short Term Temperature
0x05  0x038  1              34  N--  Lowest Average Short Term Temperature
0x05  0x040  1               -  N--  Highest Average Long Term Temperature
0x05  0x048  1               -  N--  Lowest Average Long Term Temperature
0x05  0x050  4               0  ---  Time in Over-Temperature
0x05  0x058  1              55  ---  Specified Maximum Operating Temperature
0x05  0x060  4               0  ---  Time in Under-Temperature
0x05  0x068  1               5  ---  Specified Minimum Operating Temperature

real    0m1.323s
user    0m0.061s
sys     0m0.004s

[lemonuk]

OS is Arch with kernel is Linux arch 6.6.51-1-lts #1 SMP PREEMPT_DYNAMIC x86_64 GNU/Linux

smartmontools 7.4-2.

[lemonuk]

Happens also on Ubuntu 24.04 with kernel 6.8.0-45-generic x86_64:

time smartctl -x -d sat /dev/sdc | grep -i temperature
194 Temperature_Celsius     -O---K   100   100   000    -    33 (Min/Max 14/52)

real    1m1,728s
user    0m0,033s
sys     0m0,009s