== sanity test 101b: check stride-io mode read-ahead =========================================================================== 01:02:45 (1786942965)
striped dir -i1 -c2 -H crush  /mnt/lustre/d101b.sanity

1.715303s, 4.89045MB/s
Read-ahead success for size 8192

1.996815s, 4.20099MB/s
Read-ahead success for size 16384

2.168989s, 3.86752MB/s
Read-ahead success for size 32768

1.976155s, 4.24491MB/s
Read-ahead success for size 65536

1.478439s, 5.67396MB/s
Read-ahead success for size 131072

1.373310s, 6.10831MB/s
Read-ahead success for size 262144

1.301688s, 6.44441MB/s
Read-ahead success for size 524288

1.026765s, 8.16994MB/s
Read-ahead success for size 1048576