Re: Kernel SeekCompleteErrors... Different from Re: LibPATA code issues / 2.6.15.4

["Dr. David Alan Gilbert" <linux@treblig.org>]

* Mark Lord (liml@rtr.ca) wrote:
> >>James Courtier-Dutton wrote:
> >>>
> >>>I have what looks like similar problems. The issue I have is that I 
> >>
> >>Nope.  Different issues.
> >I have changed the Subject line to indicate this so any future responses 
> >can be indicated.
> >
> >>
> >>>) #1 Sat Dec 3 18:47:19 GMT 2005
> >>>Dec 16 22:51:57 games kernel: hdc: dma_intr: status=0x51 { DriveReady 
> >>>SeekComplete Error }
> >>>Dec 16 22:52:32 games kernel: hdc: dma_intr: error=0x40 { 
> >>>UncorrectableError }, LBAsect=53058185, sector=53057951
> >>
> >>The disk really does have bad sectors in this case (above).
> >The disk has NO bad sectors. It has been checked using two different tests.
> 
> The *only* test that matters is to enable S.M.A.R.T.,
> and read out the error logs from it.

I have seen a set of drives that has reported UncorrectableErrors
and :
    * Shows the Uncorrectable error in the SMART log
    * Passes a full SMART test
    * Shows no remapped sectors
    * Passes the vendors drive test
    * Now fully passes a dd if=/dev/hdx of=/dev/null with no errors.

They were a set of 250GB SATA drives by the same vendor; I've taken
 them out one at a time as each did the same thing and replaced them
with another vendors drive.  They were all in use in RAID-1 MD 
configuration (under heavy load).

I do wonder about the 'uncorrectable error rate' that vendors report;
it doesn't seem very large - but I'll admit to not understanding its
units.  Are soft non-repeatable uncorrectable errors expected in
principal? (Pointers to a good explanation of what this actually
means would be appreciated).

I do wonder how often this happens to people and if the read succeeds
again they just blame it on software.

Dave
--
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