[rockwotj]

I recently used parallel to write a 1TB data file for testing using all cores

  seq 0 10000 | parallel dd if=/dev/urandom of=/mnt/foo/input bs=10M count=10 seek={}0

[codetrotter]

Was it noticeably different from

    dd if=/dev/urandom of=/mnt/foo/input bs=10M count=100000

in the amount of time that it took?

[rockwotj]

Yes, I had 16 cores and I gave up on the this version after several minutes. I don't remember the disk throughput difference but it was significant

[adastra22]

This should be I/o limited though.

[rockwotj]

It was a NVMe disk, so it required all cores to saturate the device