C btape скорость гораздо больше.
Wrote blk_block=5000, dev_blk_num=4999 VolBytes=322,495,488
rate=17916.4 KB/s
Wrote blk_block=10000, dev_blk_num=9999 VolBytes=645,055,488
rate=17918.2 KB/s
Wrote blk_block=15000, dev_blk_num=14999 VolBytes=967,615,488
rate=17918.8 KB/s
Wrote blk_block=20000, dev_blk_num=4499 VolBytes=1,290,175,488
rate=17673.6 KB/s
Wrote blk_block=25000, dev_blk_num=9499 VolBytes=1,612,735,488
rate=17722.4 KB/s
Wrote blk_block=30000, dev_blk_num=14499 VolBytes=1,935,295,488
rate=17755.0 KB/s