As others wrote, RAID doesn't help performance much, if at all, on the old Macs. Getting a more modern, faster single hard drive will do more than RAID will.
It's all about bottlenecks. When these machines were new, as slow as the SCSI was, the hard drives were actually slower. The hard drives got faster, but cards like the JackHammer became available, and the hard drives were still slower than the JackHammer.
For example, one of the very first Seagate Barracuda drives was the ST32550, which was a very nifty 7200RPM 2GB drive, back when 7200RPM was considered really, really fast.
However, the very best the ST32550 will deliver is about 6 MB/s. It doesn't matter whether you have the ST32550N or the ST32550W, narrow or wide electronics, the physical platters and heads can only manage 6 MB/s.
In IBM's hard drive specifications this is what is labeled the "media speed". Whatever else you say about IBM, the fact that they actually provided media speed numbers for their hard drives makes them worlds better than the other drive manufacturers in the specification department. It doesn't matter if your electronic interface will deliver 10 MB/s if your media speed is only 4 MB/s.
Anyway, so I put a NuBus Jackhammer in the Power 120 (120 MHz 8100 clone) back in the day. I put two ST32550W drives on it and built a striped array with FWB's RAID Toolkit. I got about 8 or 9 MB/s out of the combined drives. Added a third drive, and performance really didn't increase. Added a fourth drive, performance started decreasing.
So, I kept the two ST32550W (Fast & Wide) drives on the JackHammer, and put an ST32550N (Fast SCSI, Narrow) on the built-in Fast SCSI bus. This got me up to about 10 MB/s. Then I added another ST32550N to the Fast internal bus. No improvement.
Finally, I added an ST32550N to the internal/external SCSI bus. That got me up to 12 MB/s and that was the best I could ever do with ST32550 drives in the fastest NuBus machine available.
So distributing four ST32550 drives across three SCSI busses only bought me a 2X improvement in performance.
And now that years have passed, one could just buy any wide SCSI drive which supports single ended operation from the last ten years, and put it on the JackHammer and probably get better performance than I managed with that RAID.
Plus it will probably be pretty quiet. Those early 7200 RPM drives were **loud**.
It's all about bottlenecks. When these machines were new, as slow as the SCSI was, the hard drives were actually slower. The hard drives got faster, but cards like the JackHammer became available, and the hard drives were still slower than the JackHammer.
For example, one of the very first Seagate Barracuda drives was the ST32550, which was a very nifty 7200RPM 2GB drive, back when 7200RPM was considered really, really fast.
However, the very best the ST32550 will deliver is about 6 MB/s. It doesn't matter whether you have the ST32550N or the ST32550W, narrow or wide electronics, the physical platters and heads can only manage 6 MB/s.
In IBM's hard drive specifications this is what is labeled the "media speed". Whatever else you say about IBM, the fact that they actually provided media speed numbers for their hard drives makes them worlds better than the other drive manufacturers in the specification department. It doesn't matter if your electronic interface will deliver 10 MB/s if your media speed is only 4 MB/s.
Anyway, so I put a NuBus Jackhammer in the Power 120 (120 MHz 8100 clone) back in the day. I put two ST32550W drives on it and built a striped array with FWB's RAID Toolkit. I got about 8 or 9 MB/s out of the combined drives. Added a third drive, and performance really didn't increase. Added a fourth drive, performance started decreasing.
So, I kept the two ST32550W (Fast & Wide) drives on the JackHammer, and put an ST32550N (Fast SCSI, Narrow) on the built-in Fast SCSI bus. This got me up to about 10 MB/s. Then I added another ST32550N to the Fast internal bus. No improvement.
Finally, I added an ST32550N to the internal/external SCSI bus. That got me up to 12 MB/s and that was the best I could ever do with ST32550 drives in the fastest NuBus machine available.
So distributing four ST32550 drives across three SCSI busses only bought me a 2X improvement in performance.
And now that years have passed, one could just buy any wide SCSI drive which supports single ended operation from the last ten years, and put it on the JackHammer and probably get better performance than I managed with that RAID.
Plus it will probably be pretty quiet. Those early 7200 RPM drives were **loud**.