That HDD uses SMR, see https://www.seagate.com/www-content/dat ... -en_CA.pdfTook hours (days) to rsync them but once done, not much changes, so not a problem.
Reading is fine, but writing does internal rewrites depending what and how data is written.
Max I/O is 190MBps, that would be for the outer cylinders. Average I think about 120 or so, meaning reading whole 4T is (4000000/120)/3600=9.3 hours
That is about what I remember from the past when I did 4T raw copy with ddrescue from 1 HDD to the other, each on own SATA port, is less then half a day if non-SMR.
If SMR, writing drops to about 40MBps (for my 8T seagate). So for 4T about 4000000/120=28 hours minimum. But I have also seen average of about 20MBps or so for my 2.5inch WDelements (also SMR). If a bad sector, it resets, drops off the USBbus and might appear as /dev/sdb again with /dev/sda zombie.
With the earlier mentioned dual SATA adaptor, my 8T seagate is more predictable than with the older J1900 SATA controller.
Statistics: Posted by redvli — Wed Dec 18, 2024 7:29 pm