dd if=/dev/zero of=benchmark bs=64K count=32K conv=fdatasync 32768+0 records in 32768+0 records out 2147483648 bytes (2.1 GB, 2.0 GiB) copied, 9.65098 s, 223 MB/s dd if=/dev/zero of=benchmark bs=1M count=2048 conv=fdatasync 2048+0 records in 2048+0 records out 2147483648 bytes (2.1 GB, 2.0 GiB) copied, 7.35202 s, 292 MB/s