kernel: swap_pager: indefinite wait buffer - on 5.3-RELEASE-p5

[Oliver Fromme]

Uwe Doering <gemini at geminix.org> wrote:
 > Oliver Fromme wrote:
 > > If they're really identical (i.e. the same size and same
 > > geometry), then you can use dd(1) for duplication, like
 > > this:
 > > 
 > > # dd if=/dev/ad0 of=/dev/ad1 bs=64k conv=noerror,sync
 > > 
 > > The "noerror,sync" part is important so the dd command will
 > > not stop when it hits any bad spots on the source drive and
 > > instead will fill the blocks with zeroes on the destination
 > > drive.  Since it's only the swap partition, you shouldn't
 > > lose any data.
 > 
 > I would like to point out that the conclusion you're drawing in the last 
 > sentence is invalid IMHO.

I'm afraid I don't agree.

 > "indefinite wait buffer" messages at 
 > apparently random block numbers just indicate that the pager was unable 
 > to access the swap area (in its entirety!) when it wanted to.  It means 
 > that the disk drive was either dead at that point in time or busy trying 
 > to deal with a bad sector.
 > 
 > This sector could have been anywhere on the disk.  It just kept the disk 
 > drive busy for long enough that the pager started to complain.

The OP specifically said that the swap_pager messages were
the only kernel messages that he got.  That indicates that
only the swap partition is affected, because otherwise
there would have been other kernel messages indicating
I/O errors from one of the filesystems on that disk.

Best regards
   Oliver

-- 
Oliver Fromme, secnetix GmbH & Co KG, Oettingenstr. 2, 80538 München
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and may not necessarily reflect the opinions of secnetix in any way.

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