== sanity test 101b: check stride-io mode read-ahead =========================================================================== 01:51:12 (1788846672)
striped dir -i1 -c2 -H crush  /mnt/lustre/d101b.sanity

1.818848s, 4.61204MB/s
Read-ahead success for size 8192

2.449590s, 3.42449MB/s
Read-ahead success for size 16384

1.897436s, 4.42102MB/s
Read-ahead success for size 32768

1.524738s, 5.50167MB/s
Read-ahead success for size 65536

1.578039s, 5.31584MB/s
Read-ahead success for size 131072

1.426470s, 5.88068MB/s
Read-ahead success for size 262144

1.627127s, 5.15547MB/s
Read-ahead success for size 524288

1.656683s, 5.0635MB/s
Read-ahead success for size 1048576