I got an external USB3 8TB disk from Costco, namely the STEL8000401 Seagate Backup Plus Hub, the enclosure includes a USB3 HUB, and an 8TB 3.5 inch hard drive inside
upon opening the shell, I was presented with an 8TB SATA 3 6Gb/s drive with the model number ST8000DM004
According to the datasheet of the hard drive, this is an SMR drive *(Shingled magnetic recording)
Seagates markets this hard drive as a desktop hard drive, but beware, SMR drives are slow on writing, so when you are using the drive for a mostly read scenario, it may be good, but if your application is write intensive, this is not a good hard drive for that purpose
Also, from the datasheet, this drive spins at 5400RPM, opposite to my older seagate barracuda 8TB (ST8000DM002) which is a 7200 and is not an SMR drive
I will be doing some more experimentation with this drive in a bit, and post the results here
The lowdown: 130 MiB/s sequential Write, and 132 sequential read ! the older drive has a 230MiB/s sequential read
The first experiment is using PV, for those who do not know, PV is like DD but somewhat more advanced, I will be copying the drive ST8000DM002 to the new ST8000DM004, after passing the 10GB mark, the transfer speed from one disk to the other was around 130 MiB/s (Speed of writing to the new SMR drive). Again, regardless of the data, this is a byte for byte copy including blank areas, therefore this is an example of a sequential write. for comparison, writing the same data to /dev/null (read on the old drive) results in 230 MiB/s meaning the bottleneck is writing to the SMR drive. reading from the newer SMR drive to /dev/null results in 132 MiB/s which is surprisingly similar to its read speed.