On Fri, 7 Sep 2018 13:22:35 -0700 Rick Stevens <ricks@xxxxxxxxxxxxxx> wrote: > On 09/07/2018 12:48 PM, jdow wrote: > > On 20180907 11:49, Ranjan Maitra wrote: > >> On Fri, 7 Sep 2018 14:26:32 -0400 Tim Evans <tkevans@xxxxxxxxxxx> wrote: > >> > >>> On 09/07/2018 02:22 PM, Ranjan Maitra wrote: > >>> > >>>> I was doing this and it is definitely faster than rsync: > >>>> > >>>> cd /drive1 > >>>> tar cf - uncopieddir1 uncopieddir2 ... | ( cd /drive2 ; tar xf - ) > >>>> > >>>> But, after about 16 hours, I am only 229G in (out of 3.7T). This is > >>>> much slower than the other thread with USB drives which did 400GB in > >>>> 8 hours. > >>> > >>> Try this: > >>> > >>> # cd /drive1 > >>> > >>> # find . -print -depth | cpio -pdm /drive2 > >> > >> Thanks! > >> > >> So, should I cancel the other job and do this? I am not sure what to > >> do, sorry. > >> > >> Ranjan > > > > Unless the drive is sparsely filled plain old "dd" may be the quickest > > end to end operation. And you get an exact duplicate so the OS and > > filesystem on the disks won't give you any trouble if you have a mix of > > filesystems. > > > > dd if=/dev/<drive1> of=/dev/<drive2> bs=1073741824 conv=sparse,noerror & > > pid=$! > > Remember that "kill -USR1 $pid" will then tell you how much you've > > copied if you get "is done yet" anxiety. > > > > You suffer no time for directory accesses, file reads and writes, and > > all that nonsense. If you do this fairly often keep it handy as a script > > or at least an example. The only time this won't work as nicely is if > > the source and destination disks are not on the same machine. The > > slowness of the tar solution won't be a problem because the network will > > as likely as not be your limiting factor. > > Good solution, but I believe he's really hitting the USB write > speed/cache flush/bus contention issue. I doubt that filesystem overhead > has anything to do with his problem. IIRC, he's doing USB---->USB > transfers. > > This is why, when possible, I use an ESATA external drive for backups. > I try to buy laptops that have ESATA ports and I have ESATA PCIe cards > for my desktops. It's not ideal, but I've seen far too many cases where > it's simply the USB ports not keeping up. It'd be interesting for him > to install gkrellm and monitor both of the drives involved to see which > one is stalling. I'm willing to bet it's the target (write) drive (the > source drive will stop doing I/O while the target drive has I/O out the > yingyang). > > But I've been wrong before (as any reader of this forum can attest to). Hi, I have SATA drives, both internal. No USB involved. You are mixing up with the other thread. Ranjan _______________________________________________ users mailing list -- users@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to users-leave@xxxxxxxxxxxxxxxxxxxxxxx Fedora Code of Conduct: https://getfedora.org/code-of-conduct.html List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/users@xxxxxxxxxxxxxxxxxxxxxxx
