average seek time

from The Free On-line Dictionary of Computing (8 July 2008)

average seek time

   <storage> The {mean} time it takes to move the {head} of a
   {disk drive} from one {track} to another, averaged over the
   source and destination cylinders.  Usually measured in
   {milliseconds} (ms).

   The average seek time gives a good measure of the speed of the
   drive in a multi-user environment where successive read/write
   request are largely uncorrelated.

   Ten ms is common for a {hard disk} and 200 ms for an
   eight-speed {CD-ROM}.

   (2007-03-16)