Re: the >1Tb block issue

["Daniel P. Berrange" <berrange@redhat.com>]

On Tue, May 18, 2010 at 07:52:45PM +0400, Michael Tokarev wrote:
> I just re-verified it on current stable
> qemu-kvm-0.12.4.  The issue is still here,
> trivial to trigger.
> 
>  kvm-img create test.raw 1500G
>  kvm ... \
>   -drive file=test.raw,if=virtio
> 
> it fails right on the mkfs stage:
> 
>  mkfs.ext4 /dev/vdb
>  Writing inode tables: end_request: I/O error, dev vdb, sector 3145727872
>  Buffer I/O error on device vdb, logical block 393215984
>  lost page write due to I/O error on vdb
>  Buffer I/O error on device vdb, logical block 393215985
>  ...
>  Buffer I/O error on device vdb, logical block 393215993
> 
> After that it continues the mkfs process, but I doubt it will
> produce a good filesystem.
> 
> So far, only virtio has this problem.  I tested with if=ide, it's
> slower but it went much further without any error.  It's still
> running, but at this rate it will run for some hours more ;)
> At least it does not spew errors like the virtio case.

FYI this is a really useful tool for validating correctness
of the block layer.

  http://people.redhat.com/sct/src/verify-data/


Daniel
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