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Shooting from the hip here; I expect seek disparity would remain about the same, while maximum bandwidth would skyrocket.

Actually, hold on, I wonder if seek would improve very noticeably? Is seek time mostly the long-distance movements of the head, or the locating of the file in-track after the head has traveled? If it is the latter, you might be able to boost seek quite a lot.




"Seek time" as you are putting it is almost all the lateral movement of the read head (not the rotation).

Though what you're really going for here is "access time", which is "seek time" (properly defined as just the lateral movement of the head) + "rotation time" (what you call "locating of the file", which is actually just sitting there waiting for your 7,2k rpm to come around once every 4ms or so - rotating disks rotate at a constant rate, you can just do the math). A Western Digital Caviar Blue (random benchmark, I only know this because it was the last drive I bought) has a ~9ms seek time.

To recap:

Access time = seek time + rotation time ( + negligible other times, well under 10~100us)

Rotation time ~4ms (3ms for 10krpm) Seek time ~9ms (supposedly ~4 for really high end drives)

Now this is just with the technology we have right now. I do not know enough about the constraints on hardware to know if they could push the limits. For instance, if the actual write (/read?) bandwidth could theoretically be higher, would it be possible to just rotate the disk faster and/or bump up the head seek time?




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