System unresponsitive when copying HD/HD

From: Delta (
Date: Fri Feb 02 2001 - 14:57:29 EST


I backup my linux partition once a month from my second IDE drive to an
empty partition
on the first IDE disk. I have about 2.8 Gig to copy, and I use <cp -ax /
/mnt/hd> to do the copy.

While cp is copying from the second hard disk to the first hard disk,
I find my system performance
drop VERY sharply. X is sloppy, even bash takes many seconds to
respond. I using two
recent IDE disk (Fudjisu 13 gig, Maxtor 20 Gig), so I'm wondering why
the system is so slow? My mobo is a FIC SD11 and I have an athlon
550 Mhz.

I tried renicing the process priority to 20, but I don't see any
improvement on system usability.
Hard disk activity is still frenzy, even if there are other task
runnable (X, g++ jobs).
Note that I'm running as root when I'm doing the copy.

So I'd like to know why the linux kernel can't schedule the task less
I guess that copying file doesn't eat too many CPU cycles, but is
running almost all the time
in kernel mode doing I/O... Is there a way to prevent a process from
"hogging" the hard disk like that?
It's pretty annoying when the system is sluggish like that.

Thanks a lot,
Laurent Birtz <>

If you wish to reply, I'm not on the list so reply directly to me..

This archive was generated by hypermail 2b29 : Wed Feb 07 2001 - 21:00:16 EST