[ale] Errors & Celsius, WAS: Re: Spinrite, or BIOS, or something drops hdd error rate 5X

[David Tomaschik]

On 01/08/2011 08:08 AM, Paul Cartwright wrote:
> On 01/07/2011 02:51 PM, Ron Frazier wrote:
>> Just thought I'd pass along some interesting results I'm getting while
>> running Spinrite (as discussed on prior thread "Which large capacity
>> drives are you having the best luck with?") on a new drive I just
>> bought.  The utility is doing a very intensive non destructive surface
>> analysis of the whole drive, using numerous read / write data patterns.
> I was just looking at my logs, and I'm not sure if it means anything,
> and I don't know the difference between Airflow_temperature &
> temperature celsius, but my MAIN drive temp seems to be twice that of my
> 2nd drive..
> there was no entry in the syslog for sda with raw_read_error_rate... nor
> the Hardware_ECC_Recovered.
>
> Jan  8 07:59:54 paulandcilla smartd[4605]: Device: /dev/sda, SMART Usage
> Attribute: 190 Airflow_Temperature_Cel changed from 63 to 62
> Jan  8 07:59:54 paulandcilla smartd[4605]: Device: /dev/sda, SMART Usage
> Attribute: 194 Temperature_Celsius changed from 113 to 112
> Jan  8 07:59:54 paulandcilla smartd[4605]: Device: /dev/sdb, SMART
> Prefailure Attribute: 1 Raw_Read_Error_Rate changed from 103 to 99
> Jan  8 07:59:54 paulandcilla smartd[4605]: Device: /dev/sdb, SMART Usage
> Attribute: 190 Airflow_Temperature_Cel changed from 56 to 55
> Jan  8 07:59:54 paulandcilla smartd[4605]: Device: /dev/sdb, SMART Usage
> Attribute: 194 Temperature_Celsius changed from 44 to 45
> Jan  8 07:59:54 paulandcilla smartd[4605]: Device: /dev/sdb, SMART Usage
> Attribute: 195 Hardware_ECC_Recovered changed from 59 to 60
The attribute values SMART reports are not necessarily indicative of
real temperatures.  The attribute maps to the real temperature by a
scale defined by the drive manufacturer.  Below are two of my drives:

ID# ATTRIBUTE_NAME   FLAG     VALUE WORST THRESH TYPE UPDATED 
WHEN_FAILED RAW_VALUE
194 Temperature_Celsius     0x0002   152   152   000    Old_age  
Always       -       36
194 Temperature_Celsius     0x0022   112   104   000    Old_age  
Always       -       38

The value reported under RAW_VALUE is the attribute translated back to
degrees celsius.  As you can see, the attribute values are 152 and 112,
but the real temperatures are both much closer (and more reasonable) at
36 & 38.

It's also worth noting, that for all attributes, higher is better, and
the drive is considered in imminent danger of failing if any attribute
drops below its designated threshold.  Both of these drives
manufacturers' have decided that temperature NEVER indicates imminent
failure, as indicated by a 0 threshold.

HTH,
David