It seems that there is a problem with the kernel default I/O scheduler, CFQ. The following worked for me.
https://techtitbits.com/2010/04/get-rid-of-freeze-ups-during-disk-io- activity-in-ubuntu/ -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1208993 Title: Ubuntu slows down and hangs while copying file from/to USB To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/nautilus/+bug/1208993/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
