On Sun, Feb 15, 2004 at 09:56:40PM -0600, Kirk Strauser wrote:
> I use Amanda to backup an iMac running Mac OS X (10.2).  The backup runs
> perfectly, but the machine is horribly unresponsive while tar is running,
> both during the estimate and dump stages.  Renice'ing the tar processes
> doesn't seem to help, so I'm guessing that it might be an IDE DMA thing,
> although I don't know my way around Mac hardware well enough to know.
> 
> Has anyone else seen this, and hopefully found a way to lessen the impact?

Can you tell if it is cpu or i/o bound?
For example, do you have "top" or some other utility to say
if a high percent of cpu is being used and by what application(s)?

Or might it be the IDE drive as you suggest.  You might see a delay
when switching to a different shell window (as things are brought
back from swap space) are but then it seems to run pretty normal.

If something like a big dd or cat takes most of the cpu, on Solaris that
can be a quick and dirty indication that the IDE drive is not using DMA.

-- 
Jon H. LaBadie                  jon AT jgcomp DOT com
 JG Computing
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