[gentoo-user] Re: Normal disk speed?

[Nikos Chantziaras <realnc@arcor.de>]

On 09/30/2010 07:00 PM, Peter Humphrey wrote:
> On Thursday 30 September 2010 14:10:42 Florian Philipp wrote:
>
>> An HDD gets slower when you read the inner tracks.  The angular
>> velocity is constant (5400 RPM) while the tangential velocity gets
>> lower with the radius.
>
> Are you telling us that the length of a stored bit is constant? I'd have
> thought it was the time needed to read or write a bit that was constant;
> otherwise the electronics would get extremely complex. In that case it's
> the angular velocity that counts, not the linear velocity, and it
> matters not which track your data are on. (If a block goes past the head
> twice as fast, it also occupies twice the space, so you're back where
> you were.)

Uhm, no.  The higher the linear velocity, the higher the read/write 
speed.  This can be proven with any disk benchmark that can bench the 
whole disk.  You get a graph that begins low and ends high (and the 
difference between inner and outer region is substantial, almost 2:1).