Possible 32-bit PAE kernel I/O slow down with 3.3.X

I have notice significant slow downs with disk I/O on a 32-bit PAE 3.3.X kernels. The test machine has 16GB memory, Intel i5 CPU, Intel
motherboard, and an Intel 160GB SSD. I copied 536M from one partition on an SSD to another.

Test 1:
kernel 3.3.2 32-bit PAE with kernel parm mem=3G

time cp -ra testdir/ /tmp

real    0m8.989s
user    0m0.094s
sys     0m1.080s

Test 2:
kernel 3.3.2 32-bit PAE

time cp -ra testdir/ /tmp

real    1m17.068s
user    0m0.173s
sys     0m2.149s

Also I tested kernel 3.2.16 32-bit PAE with no memory limits and it was in line with test 1.

Am I doing something wrong or could something have been broken in PAE with kernel 3.3.X?

Thanks,
Joe Ceklosky

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