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> Ed W wrote: |
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> |
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>> 1) The CF card is quietly shuffling data around, so in theory it |
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>> might move a good sector onto a patch of flash which is worn out, |
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>> causing it to be corrupted on next read. |
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>> |
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> This will of course destroy a previously healthy ext2 fs. |
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> |
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> |
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> |
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>> 2) Sudden shutdowns causing the ext2 to be marked dirty and causing |
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>> subsequent problems (ie not fully read-only mounted |
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>> |
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>> To be honest, I don't know a lot about how ext2 is mounted |
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>> read-only, but option 2) above seems unlikely...? |
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>> |
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> If ext2 is mounted ro then it will never be written to by the kernel |
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> and thus never corrupted by power failure. |
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> |
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Sure - but my theory was that badly implemented wear levelling + power |
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failure during writes could perhaps cause data to be lost on a read-only |
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partition when writing to another partition on the same media? |
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I have no basis for this claim, just pondering how wear levelling is |
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actually implemented in a random off the shelf device...? |
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I agree that separate media is an excellent idea, but it's not always |
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easy to achieve using off the shelf boards? |
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Anyway, curious to hear of anyone loosing data on a read-only partition |
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in a manner like the above. It's perhaps only theoretical curiousity, |
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but... |
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Cheers |
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Ed W |
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