|
This was a question on an Operating Systems exam I had recently. I couldn't find a real clear answer through Google so I thought I'd ask the geniuses here :) Two things to take into account: there's only one process performing I/O, one harddrive and one buffer. | |||
|
feedback
|
|
The buffer is faster than the HDD and the HDD is faster at writing one long sequence than lots of short sequences. So, it's "fast" to fill the buffer (upto 3Gbit/s for SATA), then "fast" to write that as one sequence of data (~70Mb/s disk write). Comparatively it is "slow" to write lots of tiny little bits, having to wait for the HDD to line up each time (seek time typcially being ~8-12ms). | |||
|
feedback
|
|
With buffered I/O the sender just sends the data as fast as they can. Without a buffer, the sender has to be told by the receiver that they are ready for more data. | |||
|
feedback
|
