AIO with 2.6.8

["marvel@zorld.is-a-geek.org" <marvel@zorld.is-a-geek.org>]

Hello

i try to bench disk I/O with aio-stress to see if linux use or not async IO. How 
can i know if it use or not without make a bench ?

The result reporte poor performance

# WITH O_DIRECT OPTION
# ./aio-stress -b 32 -c 4  -x  -o 0 -o 1 -o 2 -o 3 -O TEST.bin
adding stage write
adding stage read
adding stage random write
adding stage random read
file size 1024MB, record size 64KB, depth 64, ios per iteration 8
max io_submit 32, buffer alignment set to 4KB
threads 1 files 1 contexts 4 context offset 2MB verification off
Running single thread version
thread 0 write totals (25.02 MB/s) 4072.00 MB in 162.74s
thread 0 read totals (89.23 MB/s) 4072.00 MB in 45.63s
thread 0 random write totals (22.61 MB/s) 4072.00 MB in 180.07s
thread 0 random read totals (60.31 MB/s) 4072.00 MB in 67.51s

# WITHOUT O_DIRECT OPTION
# ./aio-stress -b 32 -c 4  -x  -o 0 -o 1 -o 2 -o 3 TEST.bin
adding stage write
adding stage read
adding stage random write
adding stage random read
file size 1024MB, record size 64KB, depth 64, ios per iteration 8
max io_submit 32, buffer alignment set to 4KB
threads 1 files 1 contexts 4 context offset 2MB verification off
thread 0 write totals (74.51 MB/s) 4072.00 MB in 54.65s
thread 0 read totals (347.50 MB/s) 4072.00 MB in 11.72s
thread 0 random write totals (9.78 MB/s) 4072.00 MB in 416.30s
thread 0 random read totals (27.57 MB/s) 4072.00 MB in 147.69s

thanks
++