Messages in this thread | | | Date | Mon, 19 Mar 2001 15:32:31 -0500 (EST) | From | Mark Hahn <> | Subject | Re: UDMA 100 / PIIX4 question |
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> > > I have an IBM DTLA 307030 (ATA 100 / UDMA 5) on an 815e board (Asus CUSL2), which has a PIIX4 controller. > > > ... > > > My problem is that (according to hdparm -t), I never get a better transfer rate than approximately 15.8 Mb/sec.... > > > > 15MB/s for hdparm is about right.
it's definitely not right: this disk sustains around 35 MB/s.
> Yes, since hdparm -t measures *SUSTAINED* transfers... the actual "head rate" of data reads from > disk surface. Only if you read *only* data that is alread in harddrive's cache will you get a speed > close to the UDMA mode of the drive/controller. The cache is around 1Mbyte, so for a split-second > re-read of some data....
nonsequitur: the controller and disk are both quite capable of sustaining 20-35 MB/s (depending on zone.) here's hdparm output for a disk of the same rpm and density as the DTLA's:
Timing buffer-cache reads: 128 MB in 1.07 seconds =119.63 MB/sec Timing buffered disk reads: 64 MB in 2.02 seconds = 31.68 MB/sec
(maxtor dm+45, hpt366 controller) regards, mark hahn.
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