:For RAID3 that is true. For the other ones...
:
:>     performance without it - for reading OR writing.  It doesn't matter 
:>     so much for RAID{1,10},  but it matters a whole lot for something like
:>     RAID-5 where the difference between a spindle-synced read or write
:>     and a non-spindle-synched read or write can be upwards of 35%.
:
:If you have RAID5 with I/O sizes that result in full-stripe operations.
:
:-- 
:|   / o / /_  _                email:  [EMAIL PROTECTED]
:|/|/ / / /(  (_)  Bulte                Arnhem, The Netherlands 

    Well, for reads a non-stripe-crossing op would still work reasonably
    well.  But for writes less then full-stripe operations without
    spindle sync are going to be terrible due to the read-before-write
    requirement (to calculate parity).  The disk cache is useless in that
    case.

                                                -Matt


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