Patent ID: 6112255
Filing Date: 2000-08-29
Classification: G06F

Abstract:
A storage device comprising a cyclic, tracked storage medium (9); means for accessing said medium (7,8); said device further comprising:a buffer having first and second addressable segments, wherein mirror locations in said addressable segments share the same address;a copy-back path (8,7,15) including said accessing means for staging a first block recorded at a predetermined track address on the storage medium to a location in the first buffer segment (5B) and subsequently for staging (17,3,19) the first block to a device interface (3);a recording path (2,3,11) also including said accessing means for writing a second block received from the device interface to a mirror location in the second buffer segment (5A) corresponding to the location in the first buffer segment, and subsequently for writing (13,7,8) said second block to the predetermined track address on the storage medium; andmeans (4,6,11,21) responsive to external commands received through the device interface (3) for operatively invoking said copy-back and recording paths, for logically combining a copy of the second block as it is being written to the location in the second buffer segment with the first block as it is concurrently being read from the mirrored location in the first buffer segment, and for rendering said logically combined block available at the device interface (3) in the copy-back path.