io priority

I speak english very bad.
openSuSe 10.3
old computer(5 years):
HD IDE
2.6.22.17-0.1-default
linux-qnsw:/home/dim # cat /sys/block/sdb/queue/scheduler
noop anticipatory deadline [cfq]
linux-qnsw:/home/dim # cat /sys/block/sda/queue/scheduler
noop anticipatory deadline [cfq]

I played io priority yesterday.
1.I run ionice -c1 -n0 konqueror and start copy.
2.I run konqueror and start copy.
But speed of copy is identical.
It is wrong.
What wrong?