Hi Ralf,
> I am copying from an internal SATA SSD via USB 3 to an external SATA WD
> Blue, a 3.5" CMR HDD.
>
> The first part “cp -ai /mnt/winos7/” (see [*1]) took about 70 minutes
> for 188 GiB, almost all files are quite small. The second part “cp -ai
> /mnt/winos10/” (see [*1]) should copy about 100 GiB small files + about
> 740 GiB for a single vbox vdi file. The about 100 GiB small files were
> copied and about 310 GiB of the vdi file were also already copied, at
> 03:30, so for about 410 GiB it took about 9 hours. I think this is
> taking far too long.
> Does anyone have an idea?
No, though I tend to use rsync(1) on large copies which might need
continuing, or checking that the copy is identical after an
unmount/mount to ensure the media is being read.
Have you checked what SMART data can be accessed on the drives, given
the possible restrictions like USB?
> %Cpu(s): 1.8 us, 0.8 sy, 0.0 ni, 84.3 id, 12.9 wa, 0.1 hi, 0.1 si, 0.0
> st
12.9% wait is waiting for I/O. I'm guessing you have eight cores as
1/8 = 0.125 CPU. IOW, the cp(1) is I/O bound.
You may find ‘vmstat 1’ interesting to monitor the number of blocks
I/O'd, ‘bi’ and ‘bo’. And
dstat -cd -Dtotal,sda1,sda2
handy to monitor the about of waiting, ‘wai’, and the data moved between
block devices.
--
Cheers, Ralph.
