Comment 18 for bug 709245

I have added nohlt and seems no any changes wrt. usb storage performance.

But the following test is interesting, just run a 'busy' in background and increas usb
storage performance triple or 4 times, and killing the 'busy' task will make usb
storage performance poor like before.

see my test below:

root@tom-panda:~# ifconfig
lo Link encap:Local Loopback
          inet addr:127.0.0.1 Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING MTU:16436 Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:0 (0.0 B) TX bytes:0 (0.0 B)

root@tom-panda:~# dd if=/dev/sda iflag=direct of=/dev/null bs=128K count=32
32+0 records in
32+0 records out
4194304 bytes (4.2 MB) copied, 5.9715 s, 702 kB/s
root@tom-panda:~# cat /proc/cmdline
ro elevator=noop vram=32M mem=456M@0x80000000 mem=512M@0xA0000000 root=UUID=a957f519-7a09-48d9-
a60d-b15883901edf fixrtc quiet splash console=ttyO2,115200n8 serialtty=ttyO2 earlyprintk
root@tom-panda:~# ./busy&
[1] 1183
root@tom-panda:~# cat busy
#/bin/sh

x=1
while [ true ]
do
  x=$(( $x + 1 ))
done
root@tom-panda:~# dd if=/dev/sda iflag=direct of=/dev/null bs=128K count=32
32+0 records in
32+0 records out
4194304 bytes (4.2 MB) copied, 0.771301 s, 5.4 MB/s
root@tom-panda:~# kill -9 1183
root@tom-panda:~# sleep 3
[1]+ Killed ./busy
root@tom-panda:~# dd if=/dev/sda iflag=direct of=/dev/null bs=128K count=32
32+0 records in
32+0 records out
4194304 bytes (4.2 MB) copied, 3.40616 s, 1.2 MB/s