And, in related news, The Register has two articles on a working 28-year-old Seagate ST-412 disk drive from an IBM 5156 PC expansion box. They point out, as I have, that disk drives are not getting faster as fast as they are getting bigger:
The 3TB Barracuda still has one read/write head per platter surface and each head now has 300,000MB to look after, whereas the old ST-412 heads each have just 5MB to look after.Revised 4/12/11 to make clear that the disk drive still works.
The Barracuda will take longer today to read or write an entire platter surface's capacity than the 28-year-old ST-412 will. We have increased capacity markedly but disk I/O has become a bottleneck at the platter surface level, and is set to remain that way. The Register
I personally find that the B/W and other scaling issues are particularly tricky problem to articulate to some systems, and even storage researchers, when taken in the context of long-term digital archiving.
I frequently am told "Well who cares! The bits are cheap, we can just store more of them!" without acknowledging that locating, migrating and protecting data is becoming increasingly difficult with the growing I/O bottleneck.
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