On Mon, 29 Nov 1999, Bruce Martin wrote:

> I am testing hard disk transfer speeds on an arm32 (EBSA285) system under
> NetBSD with the Promise Ultra 33 IDE controller. Can anyone out there tell
> me the fastest transfer rates they have got, how they managed to get them,
> and what hardware they were using.

Just for comparison with another platform that seems able to max
out disks pretty well, I get fairly reasonable rates from an IDE
drive on my Alpha PC164 (500 MHz 21164, 128 MB RAM):

              -------Sequential Output-------- ---Sequential Input-- --Random--
              -Per Char- --Block--- -Rewrite-- -Per Char- --Block--- --Seeks---
Machine    MB K/sec %CPU K/sec %CPU K/sec %CPU K/sec %CPU K/sec %CPU  /sec %CPU
          100 11598 79.5 11738 19.9  2547  5.5 11391 72.8 11849 15.0 112.2  1.8

cia0 at mainbus0: DECchip 2117x Core Logic Chipset (ALCOR/ALCOR2), pass 3
cia0: extended capabilities: 21<DWEN,BWEN>
cia0: using BWX for PCI config access
pci0 at cia0 bus 0
pci0: i/o enabled, memory enabled
pciide0 at pci0 dev 11 function 0: CMD Technology PCI0646
pciide0: bus-master DMA support present
pciide0: primary channel wired to compatibility mode
wd0 at pciide0 channel 0 drive 0: <QUANTUM FIREBALL EX3.2A>
wd0: drive supports 16-sector pio transfers, lba addressing
wd0: 3079MB, 6256 cyl, 16 head, 63 sec, 512 bytes/sect x 6306048 sectors
wd0: 32-bits data port
wd0: drive supports PIO mode 4, DMA mode 2, Ultra-DMA mode 2
wd0(pciide0:0:0): using PIO mode 4, DMA mode 2 (using DMA data transfers)

For comparision, here's what I get on the same machine from a pair
of modern Barracudas (7200 RPM) striped using ccd (interleave 96)
on an Adaptec 2940UW:

              -------Sequential Output-------- ---Sequential Input-- --Random--
              -Per Char- --Block--- -Rewrite-- -Per Char- --Block--- --Seeks---
Machine    MB K/sec %CPU K/sec %CPU K/sec %CPU K/sec %CPU K/sec %CPU  /sec %CPU
          100 14354 97.9 23755 46.2  5344 11.6 12948 94.3 28164 38.2 161.6  2.7

So it seems at this point that there's not much use in buying a
single SCSI disk; IDE is much cheaper and very nearly as fast.

cjs
--
Curt Sampson  <cjs@cynic.net>   917 532 4208   De gustibus, aut bene aut nihil.
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