Thread: How harddisk writes files?

Given a hard drive with p number of sectors on each track, q number of tracks on each platter, and a total of r different platters. Suppose that the hard drive has one read/write head for each platter. Data cannot be read/written in parallel in different tracks of the same platter, but data of the same track number and sector number on different platters can be read/written simultaneously.

Suppose file length is the same as the one platter length and you have already partitioned your file into blocks with each block having the same size as the sector size. which option gives the shortest time to write the file?

Option A
place the file on one platter only and by putting the first p blocks on different sectors of the same track and then another p blocks on a different track, in the same fashion.
(linear writing)

Option B
first partition the blocks in r groups, and each group is further partitions into q subgroups with each having p number of blocks. Then, place different subgroups on the same track of different platters. Then to a different track and repeat the same operation.
(parallel writing)


Option B seems to be faster as parallel writing(writing into platters at the same time), but it has longer seeking time than option A. which factor domains?
in this case,
I wondered why transferring multiple files generally takes longer time than a single big file of same size.