I beleive this is a well-known "feature" in the kernel itself. It prioritizes file operations.
I can confirm this going on with .tar backups and beleive it's the same phenomenon. When working with large files, the kernel uses so much resources that the user interface part becomes sluggish or unresponsive. -- File move causes 100% CPU usage https://bugs.launchpad.net/bugs/236141 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs