hdparm -I /dev/sd[g-i]|grep -E 'Model Number:|Nominal Media Rotation Rate:'
Model Number: Hitachi HUS724040ALE641
Nominal Media Rotation Rate: 7200
Model Number: WDC WD50PURX-64T0ZY0
Nominal Media Rotation Rate: 5700
Model Number: WDC WD30EFRX-68AX9N0
dd if=/dev/sdg of=/dev/null bs=1M count=10000 status=progress
10430185472 bytes (10 GB, 9.7 GiB) copied, 61 s, 171 MB/s
10000+0 records in
10000+0 records out
10485760000 bytes (10 GB, 9.8 GiB) copied, 61.3236 s, 171 MB/s
dd if=/dev/sdh of=/dev/null bs=1M count=10000 status=progress
10364125184 bytes (10 GB, 9.7 GiB) copied, 57 s, 182 MB/s
10000+0 records in
10000+0 records out
10485760000 bytes (10 GB, 9.8 GiB) copied, 57.6876 s, 182 MB/s
dd if=/dev/sdi of=/dev/null bs=1M count=10000 status=progress
10414456832 bytes (10 GB, 9.7 GiB) copied, 68 s, 153 MB/s
10000+0 records in
10000+0 records out
10485760000 bytes (10 GB, 9.8 GiB) copied, 68.4405 s, 153 MB/s
dd if=/dev/sdg of=/dev/null bs=1M count=10000 status=progress skip=$((3500 * 1000))
10387193856 bytes (10 GB, 9.7 GiB) copied, 103 s, 101 MB/s
10000+0 records in
10000+0 records out
10485760000 bytes (10 GB, 9.8 GiB) copied, 103.972 s, 101 MB/s
dd if=/dev/sdh of=/dev/null bs=1M count=10000 status=progress skip=$((4500 * 1000))
10468982784 bytes (10 GB, 9.8 GiB) copied, 94 s, 111 MB/s
10000+0 records in
10000+0 records out
10485760000 bytes (10 GB, 9.8 GiB) copied, 94.1422 s, 111 MB/s
dd if=/dev/sdi of=/dev/null bs=1M count=10000 status=progress skip=$((2500 * 1000))
10473177088 bytes (10 GB, 9.8 GiB) copied, 117 s, 89.5 MB/s
10000+0 records in
10000+0 records out
10485760000 bytes (10 GB, 9.8 GiB) copied, 117.154 s, 89.5 MB/s