Short SMART check causes disk op timeouts

martinko gamato at
Mon Oct 27 12:55:04 PDT 2008

martinko wrote:
> Jeremy Chadwick wrote:
>> On Mon, Oct 27, 2008 at 07:52:01PM +0100, martinko wrote:
>>> Jeremy Chadwick wrote:
>>>>>>> Now, does the timeout cause loss of any data? Is there anything 
>>>>>>> besides
>>>>>>> disabling the testing that I can do about it?
>>>>>> Do you understand what short and long offline tests actually do 
>>>>>> and what
>>>>>> they're used for?  :-)  If so, you'd know that running them 
>>>>>> periodically
>>>>>> is more or less silly (IMHO).
>>>>> I do not, not completely :) I think I have just copied the settings 
>>>>> from
>>>>> somewhere and only just tweaked it a bit whenever I have added a disk.
>>>> Let me know if you figure out who or what online resource solicited
>>>> adding daily short/long tests, as I'd like to talk to them about their
>>>> decision.  I have a feeling whoever thought it up felt that the tests
>>>> were performing entire sector scans of the entire disk, which is simply
>>>> not the case.
>>> Hallo,
>>> Reading this thread I checked my config to find this: ;-)
>>> #/dev/ad0 -a -n standby,q -o on -S on -s (S/../.././02|L/../../7/03) 
>>> -m  root    # ++ 2006-11-03 mato
>>> /dev/ad0 -a -o on -S on -s (S/../.././02|L/../../7/03) -m root  # ++  
>>> 2006-11-03 mato
>>> I believe I came up with the settings after reading manual page /  
>>> documentation of the tool.
>> Can you explain why you're doing this?  So far no one's provided a
>> reason *why* they're doing short and long offline scans on a daily
>> basis.  I'm under the impression the conclusion was reached like this:
>> "man smartd.conf ... oh, -s, a neat thing, let's enable it".
>> There are negative repercussions to doing tests of this nature at such
>> regular intervals.  Once-a-week is borderline acceptable; once a month
>> would be quite reasonable.  I'd love to know what kind of affect daily
>> tests have on MTBF; I can imagine it's reached much sooner with this.
>> The main point of smartd is to monitor SMART attribute changes.  If
>> you're concerned about the health of your hard disk, you should be
>> looking at your logs and not relying on things like automatic short/long
>> tests.  Most SMART attributes are updated immediately and not during an
>> offline test, and all of those attribute changes will be logged.
> You asked Miroslav about source of his configuration.  And as it is very 

^^^^^^^^ I meant Vaclav, of course, Miroslav's email just arrived. :)

> similar to mine I think we both have it from smartd documentation. Where 
> else to look for information?  It's a usual source.  So if you think 
> it's wrong please contact the authors, we're obviously just users.
> Thanks.
> M.
> PS: Btw, long offline scan is scheduled on weekly basis, not daily. If 
> it's good or not I do not know.

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