Read speed with dd:

# dd bs=1M count=5120 if=/dev/nvme0n1 of=/dev/null
5120+0 records in
5120+0 records out
5368709120 bytes (5.4 GB, 5.0 GiB) copied, 33.6467 s, 160 MB/s

# taskset -c 0-7 dd bs=1M count=5120 if=/dev/nvme0n1 of=/dev/null
5120+0 records in
5120+0 records out
5368709120 bytes (5.4 GB, 5.0 GiB) copied, 3.51555 s, 1.5 GB/s

# taskset -c 8-15 dd bs=1M count=5120 if=/dev/nvme0n1 of=/dev/null
5120+0 records in
5120+0 records out
5368709120 bytes (5.4 GB, 5.0 GiB) copied, 33.6982 s, 159 MB/s

# taskset -c 24-31 dd bs=1M count=5120 if=/dev/nvme0n1 of=/dev/null
5120+0 records in
5120+0 records out
5368709120 bytes (5.4 GB, 5.0 GiB) copied, 33.6506 s, 160 MB/s

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Write speed with dd:

# dd bs=1M count=5120 if=/dev/zero of=/dev/nvme0n1
5120+0 records in
5120+0 records out
5368709120 bytes (5.4 GB, 5.0 GiB) copied, 6.41391 s, 837 MB/s

# taskset -c 0-7 dd bs=1M count=5120 if=/dev/zero of=/dev/nvme0n1
5120+0 records in
5120+0 records out
5368709120 bytes (5.4 GB, 5.0 GiB) copied, 6.37381 s, 842 MB/s

# taskset -c 8-15 dd bs=1M count=5120 if=/dev/zero of=/dev/nvme0n1
5120+0 records in
5120+0 records out
5368709120 bytes (5.4 GB, 5.0 GiB) copied, 6.52113 s, 823 MB/s

# taskset -c 24-31 dd bs=1M count=5120 if=/dev/zero of=/dev/nvme0n1
5120+0 records in
5120+0 records out
5368709120 bytes (5.4 GB, 5.0 GiB) copied, 6.38797 s, 840 MB/s