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Am 03.05.2011 19:54, schrieb Evgeny Bushkov: |
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> Hi. |
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> How can I find out which is the parity disk in a RAID-4 soft array? I |
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> couldn't find that in the mdadm manual. I know that RAID-4 features a |
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> dedicated parity disk that is usually the bottleneck of the array, so |
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> that disk must be as fast as possible. It seems useful to employ a few |
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> slow disks with a relatively fast disk in such a RAID-4 array. |
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> |
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> Best regards, |
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> Bushkov E. |
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> |
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|
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You are seriously considering a RAID4? You know, there is a reason why |
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it was superseded by RAID5. Given the way RAID4 operates, a first guess |
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for finding the parity disk in a running array would be the one with the |
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worst SMART data. It is the parity disk that dies the soonest. |
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From looking at the source code it seems like the last specified disk is |
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parity. Disclaimer: I'm no kernel hacker and I have only inspected the |
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code, not tried to understand the whole MD subsystem. |
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|
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Regards, |
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Florian Philipp |
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