For RAID-1 it's a killer (for writes), I agree.
But I really doubt it would be so horrible for RAID-5 - after all, it's only
one extra block (the parity block) for each N-1 blocks written (for an N disk
RAID-5). The penalty should be less, the more disks you have in the array.
But seriously, has anyone out there ever seen a hardware RAID controller with
a *sustained* RAID-5 thoughput of more than 60 MB/sec ? Not that I think it
is impossible, but I've never heard about it. Enlighten me, please, and not
with marketing numbers...
>
> > By the way, has anyone tried such larger multi-controller setups, and t=
> > ested
> > the bandwidth in configurations with multiple PCI busses on the board, =
> > versus a
> > single PCI bus ?
>
> With 2.4 yes. With all the 2.5 changes no.
Did you get any speedup ? Were you close to PCI bus saturation in the one-bus
scenario ?
--
................................................................
: jakob@unthought.net : And I see the elder races, :
:.........................: putrid forms of man :
: Jakob Østergaard : See him rise and claim the earth, :
: OZ9ABN : his downfall is at hand. :
:.........................:............{Konkhra}...............:
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