Olaf Fra;czyk wrote:
> I have linux 2.4.20 + XFS from CVS 09-Jan-2003.
> System is based on RedHat 8.0.
> Motherboard ASUS A7V266A (via KT266A chipset)
> 512MB RAM
> 2 IBM SCSI disks connected to Adaptec 2940U2W
> CD-RW, DVD-RAM connected to the same adaptec card
> 2 IBM IDE disks connected to motherboard controller
> If I copy disk /dev/hda to /dev/hdc:
> cat /dev/hda > /dev/hdc the system becomes __highly__ unresponsive
> Processor is about 90 % idle
> Load average is about 5
> Working with X is impossible (about 1 second freeze every 1-2 seconds).
> As the root partition is also XFS I have no possibility to load vanilla
> kernel and try with it. I also have no free partition on SCSI disk to
> install fresh system with vanilla kernel for testing.
> renice -19 for X makes no difference.
> Does anyone has idea why is it happening? Or maybe this is "normal"
> linux behaviour?
> I will have some free time later and I'll grab latest CVS and try it.
> Olaf Fraczyk
Do you have dma enabled on your IDE disks? I can't think of any reason
off the top of my head why a cat from hda -> hdc should be affected by
XFS, as you aren't using the filesystem for that - it's just reading the
raw device. Make sure dma is enabled on hda and hdc and see if that
helps: hdparm -d1 /dev/hda /dev/hdc