Messages in this thread | | | Subject | Re: [dm-devel] [PATCH 0/4] dm verity: add support for error correction | From | Zdenek Kabelac <> | Date | Fri, 6 Nov 2015 22:05:24 +0100 |
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Dne 6.11.2015 v 21:27 Sami Tolvanen napsal(a): > On Fri, Nov 06, 2015 at 08:20:15PM +0100, Zdenek Kabelac wrote: >> i.e. you have 1G of space - you want to give 250MB as 'redundancy' - >> so create 4 partition....
well data safety has it's price - user should choose what he prefers - more games and videos or more safety...
> > We cannot afford to set aside 25% of read-only partition space for > redundancy on mobile devices, and would rather not impact performance > any more than dm-verity already does. With error correction we have > 0.8% space overhead in our use case and no performance degradation if > the partition is not corrupted. >
I'm probably missing here some hw knowledge here - but if you loose a flash block of some size - then you typically get 'error' for all bytes the sector/block.
So how do you want to correctly 'restore' missing full sectors with just 0.8% data overhead ??
Or is the device which fails to correct block returning something 'still usable' (since e.g. SATA disk certainly not)
Zdenek
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