DMA RAID query

wieseltux23 wieseltux23 at gmail.com
Wed Mar 8 21:49:10 UTC 2006


www.wolfspakt.de/spiel.php?id=7358







On Wed, 08 Mar 2006 15:49:29 -0500
Phillip Susi <psusi at cfl.rr.com> wrote:

> It isn't that simply having the drives there slow things down, it is 
> using them.  IDE can only talk to one of the two drives at a time, so if 
> you are reading data from the cdrom, or burning a disc in the writer, 
> then the hard drive throughput will drop like a rock. 
> 
> dave s wrote:
> > Hi all,
> >
> > I have a working RAID 1 setup
> >
> > hda HDD 180GB RAID
> > hdb DVD burner/reader
> > hdc HDD 180GB RAID
> > hdd DVD reader
> >
> > hdparm -tT /dev/hda and hdc gives ...
> >
> > 1278MB/sec cashed reads
> > 62MB/sec bufferd disk reads
> >
> > Which seems respectable for new 7200 Hitachi drives. (I did not setup DMA, my 
> > BIOS did it for me) I was warned never to mix a HDD & a CD/DVD burner as it 
> > degrades the HDD speed.
> >
> > I removed hdb and hdd, rebooted and did another hdparm -tT and got the same 
> > results.
> >
> > I was going to install a PCI ATA controller for the two DVD drives but am 
> > unsure now if it is worth it, can anyone comment (1st time RAID user :)
> >
> > Dave
> >
> >   
> 
> 
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 189 bytes
Desc: not available
URL: <https://lists.ubuntu.com/archives/ubuntu-users/attachments/20060308/1a504455/attachment.pgp>


More information about the ubuntu-users mailing list