Messages in this thread | | | Date | Thu, 13 Feb 1997 09:28:24 +0100 | From | Christian Rienecker <> | Subject | Re: IDE Disk Problems |
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On Wed, 12 Feb 1997 travis@zeus.rwii.com wrote:
> > Mime-Version: 1.0 > Content-Type: text/plain; charset=us-ascii > Date: Wed, 12 Feb 1997 18:42:40 -0500 > From: Travis Woodbury <travis@rwii.com> > > > > [snip] > > > Again, on the performance side, I get upwards of 25MB/s on either of my > > > Seagate UltraWide scsi devices; a measurement that you are very unlikely > > > to see on _any_ IDE drive (note: this is while the system is under > > > considerable load, too). > > > > > > > How did you measure that 25MB/s ? My 2 Maxtor IDE 2.0G's give me an > > 'hdparm -T' value (cached xfer) of 32.0MB/s on a Micronics PCI/IDE > > M54HI-Plus with a iP200 cpu. (My 'hdparm -t' >4.0 ie non-cached xfer) :-) > > Whats the cached transfer rate matter. Its the overall throughput that > matters. > > With a Buslogic BT-958 and a Seagate Barracuda (ST32171W) I get just over 8.5 > MB/s > with hdparm...no, thats not the cached rate. Unfortunately it didnt come cheap > > BT-958 $241 > ST32171W $695 > > IDE seems to be the right choice for the everday workstation. I get great > throughput > with the Quantum Fireballs 6.50 MB/s. $252 > > But for a small server or heavily used work station an Ultra Wide bus of fast > drives > kicks ass. > > One of these days I'll have find the time to stripe two of those ST32171W's:) > > Not that this affects kernel development:) > > -Travis Woodbury > > > Could it be that you are confusing MBytes with MBits ? 'Cause even with PIO mode 4 an EIDE bus cannot exceed 16 MBytes/sec regardless of where the data comes from. Furthermore, according to my sources there is no no SCSI HD which exceeds 10 MBytes/sec real transfer (fram disk not cache) despite having the theoretical limit of 40 MBytes/sec for an UltraWide controller.
CR.
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