On 07/08/2020 15:47, Haines Brown wrote:
> Cron automatiically backs up some partitions on my HD by means of a
> script. Not sure of the size of thse backupos, but perhaps 300 Mb.
>
> I have been doing the backups to an external WD USB drive, and they
> took around 3 hours. However, I became nervous about the condition of
> the drive which is quite old, and so bought a 2 Tb replacement. Now
> the back up takes 10 hours.
>
> The only thing that I can think of that might account for its being
> slow is that my old WD drive was formatted ext4, but I thought best to
> leave my new drive with NTFS.
>
> This causes a problem in that if the backup drive happens to be
> mounted, the mount command in my script no longer just tells me so
> and proceeds with the backup, but instead hangs.
>
> The other problem may be that for some reason the disk being NTFS
> drastically slows the backup. So it occurred to me to make the command
> in the script to mount the drive: mount -t ntfs /mnt/backup (I have
> the drive's UUID in fstab). But when I check /proc/filesystems, ntfs
> apparently is not recognized by the kernel. However, my impression
> is that my having the ntfs-3g rw driver installed should enable me to
> mount a NTFS partion wtihout problem or need for the -t ntfs option.
>
> I checked my CPU instuctions/second. The services started at bootime
> have not changed. The # top command does not show any problems. $ free
> suggests I'm not demanding too much of my RAM. # iotop shows that my
> backup process I/O demand on the kernel runs 50-100%. The kworker
> flush can be 100%. My guess is that these figures are to be expected.
> I run the backup at a time when no other significant processes are
> running.
>
Do you use the USB drive on Windows, if not, just reformat it to ext4,
ntfs-3g is a FUSE system, it isn't a fast as you would like.

Rowland