3.11 Attribute ID 188: Command Timeout Count

Normalized Command Timeout Count = 100 - Command Timeout Count.

This attribute tracks the number of command time outs as defined by an active command being interrupted by a HRESET and COMRESET or SRST or another command.

The normalized value is only computed when the number of commands is in the range 10^3 to 10^4. The CommandCount and ErroCount are cleared when Number Of Commands reaches 10^4. The error count used to compute normalized value is not reported in attribute Raw value. It is reported in vendor info area of Attribute sector, bytes 474:475.

If Command Timeout Count is > 99, normalize value of 1 is reported. The initial Worst Value is set to 0xFD as a special case.

Raw Usage

Raw [1 - 0] = Total # of command timeouts, with Max hold of FFFFh

Raw [3 - 2] = Total # of commands with > 5 second completion, including those > 7.5 seconds

Raw [5 - 4] = Total # of commands with > 7.5 second completion

I'm assuming that the drive is a Seagate.

A raw value of 854712254691 equates to 0x00C700D200E3 in hexadecimal.

http://www.google.com/search?q=854712254691+in+hex

That is, the 3 components are ...

0x00C7 (= 199 decimal)
0x00D2 (= 210)
0x00E3 (= 227)

The bottom line is that Command Timeouts are a sign that the drive is struggling. I would backup regularly.

The best raw value is zero, ie no timeouts. As for how to avoid them, that is beyond the user's control.