Thanks @peterrus! I can confirm that using swapoff completely removes the hanging and stuttering during heavy disk IO.
I don't see this only during file copy. Extracting archives, for example, or saving virtual machine state to disk cause the same kind of stuttering and hanging. It was impossible for me to import an .ova image into VirtualBox when swap was on because my system became unresponsive. After turning swap off, I can use virtualbox again!! -- 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/linux/+bug/1208993/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs