results_odirect_ra4096

text/plain

Filename: results_odirect_ra4096
Type: text/plain
Part: 4
Message: Re: Slow count(*) again...
[craig@ayaki tmp]$ echo -n "Readahead: "; sudo blockdev --getra /dev/sda; for (( x = 2; x < 14; x++ )); do echo $((1<<x))kb blocks; time ./io $((1<<x)) test_file; done
Readahead: 4096
4kb blocks
read: Success

real	0m37.465s
user	0m0.037s
sys	0m12.810s
8kb blocks
read: Success

real	0m21.776s
user	0m0.024s
sys	0m8.362s
16kb blocks
read: Success

real	0m14.085s
user	0m0.012s
sys	0m5.463s
32kb blocks
read: Success

real	0m10.661s
user	0m0.006s
sys	0m4.496s
64kb blocks
read: Success

real	0m9.778s
user	0m0.005s
sys	0m3.768s
128kb blocks
read: Success

real	0m9.730s
user	0m0.000s
sys	0m3.373s
256kb blocks
read: Success

real	0m10.371s
user	0m0.000s
sys	0m3.140s
512kb blocks
read: Success

real	0m9.847s
user	0m0.000s
sys	0m3.169s
1024kb blocks
read: Success

real	0m9.880s
user	0m0.000s
sys	0m3.098s
2048kb blocks
read: Success

real	0m11.124s
user	0m0.000s
sys	0m3.001s
4096kb blocks
read: Success

real	0m11.653s
user	0m0.000s
sys	0m2.765s
8192kb blocks
read: Success

real	0m11.503s
user	0m0.001s
sys	0m2.680s