SATA and HDParm

[Ow Mun Heng]

On Thu, 2004-11-25 at 10:48, Peter Teuben wrote:
> On Thu, 25 Nov 2004, Ow Mun Heng wrote:
> 
> > Guys,
> > 
> > 	I've heard that hdparm does not run on scsi drives.(SATA included)
> > 
> > I've tried to use hdparm anyway, and it gave results. But the results
> > are seriously _out_of_this_world (for me).
> > 
> > Can anyone validate these?
> 
> try running it successive times. On my SATA i see the disk reads continue
> to grow by the amount of the first measurement. I'm also getting an
> error message though, 

ditto for the error message as well.
> 
> Timing buffered disk reads:  156 MB in  3.06 seconds =  50.90 MB/sec
> Timing buffered disk reads:  302 MB in  3.01 seconds = 100.45 MB/sec
> Timing buffered disk reads:  442 MB in  3.02 seconds = 146.19 MB/sec
> ....
> as if hdparm remembers the buffer it read the last time.... Despite that,
> 51MB/sec is not bad. But your 146.9 sounds like the 3rd measurement :-)

The readings are erratic. like yours. Worst case is also 50MB/sec.