xfs, 4 NVMe striped devices, stripe size 64k, hyperthreading disabled Sequential read and sequential write on a XFS filesystem. We see that there is some overhead when reading compared to the raw device. QAT underperforms. dd if=/dev/zero of=/mnt/test/file bs=1M status=progress dd if=/mnt/test/file of=/dev/null bs=1M status=progress raw device: sequential read: 8.8 GB/s busy: 1.576038% idle: 98.305875% irq: 0.109230% sequential write: 4.4 GB/s busy: 0.963663% idle: 98.954620% irq: 0.046966% dm-crypt, aes-ni, 4096 sequential read: 4.7 GB/s busy: 2.412217% idle: 97.539699% irq: 0.064529% sequential write: 4.5 GB/s busy: 10.007140% idle: 89.816142% irq: 0.126174% dm-crypt, qat, 4096 sequential read: 3.1 GB/s busy: 2.130121% idle: 97.390935% irq: 0.450974% sequential write: - the dd process repeatedly stalls for a few seconds during this test 1.9 GB/s busy: 3.382846% idle: 93.382349% irq: 1.837052%