Ski Harrison wrote:
> I still get 17MB/sec. I would think I should get
> something like you mention below, 23-24MB/sec, double the plain
> jane WD 4gig DMA33 drive.
Though I still don't know specifically how you can tell whether you are in
udma66 mode or not, from all of my research there's no way you should expect
your 17MB/sec in udma33 to translate to 24MB/sec in udma66. That's a 41%
speed up just from the bus transfer speed, which just isn't going to happen
as long as we're still talking about transfer rates under the theoretical
maximum of udma33... 33MB/sec. I have heard people saying they've seen
5-10% increases in speed, which I think is all you'll see until drive
physical transfer rates start exceeding 33MB/sec.
Also, Jan mentioned test speeds from both inner cylinders and outer
cylinders. 18MB was the number for inner cylinders, which is very close to
your own number. Does hdparm -tT /dev/hdc test from the inner or outer
cylinders? If it starts from block 0, it will be reading from the inner
ones, no? As drives spin at a constant speed, but there is more surface
area on the outside of the platter, more data is read (faster MB/sec) per
one rotation.
Tom
