Bear in mind that what you are calling "true hardware raid" is really a microprocessor programmed to do the raid algorithims. Usually these microprocessors are stretched to the limit to handle the throughput of modern udam drives. I don't know but I suspect that the small overhead use in the mmu for software raid has far more and faster throughput than any of these dedicated microprocessors..... and, you can see the code and know it is bug free or will be if you report the
Nod... many hardware RAIDs are turning out this way. A certain vendor whose name does -not- start with 'A' manages to make their hardware RAID perform so poorly, it is _half_ the speed of a software RAID using the same drives, on a single non-RAID Adaptec SCSI controller.
Most hardware RAID isn't 100% ASIC, but rather a general ASIC and firmware with the RAID code in it.
OTOH, hardware RAID really wins for situations like RAID-1, where you can -halve- the amount of data going across the PCI bus versus software RAID.
Jeff
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