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On Thursday 30 September 2010 14:10:42 Florian Philipp wrote: |
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> An HDD gets slower when you read the inner tracks. The angular |
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> velocity is constant (5400 RPM) while the tangential velocity gets |
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> lower with the radius. |
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Are you telling us that the length of a stored bit is constant? I'd have |
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thought it was the time needed to read or write a bit that was constant; |
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otherwise the electronics would get extremely complex. In that case it's |
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the angular velocity that counts, not the linear velocity, and it |
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matters not which track your data are on. (If a block goes past the head |
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twice as fast, it also occupies twice the space, so you're back where |
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you were.) |
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That's the way it was with our imposing new 2MB disks in 1974, anyway. |
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They occupied boxes four feet tall and six feet long, and had external |
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air systems; I was one of those responsible for the maintenance; we were |
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sent on a training course specifically for the disks. I can't remember |
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who made them, but they were part of a Ferranti Argus 500 system at the |
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then national grid control centre. |
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Maybe technology has changed since then. |
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-- |
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Rgds |
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Peter. Linux Counter 5290, 1994-04-23. |
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