I'm wondering why I can't set ionice for cp. ionice -c2 -n0 cpI run this command and I get: cp: missing file argument  Try `cp --help' for more informationWhy? I saw topic here about nice and similiar command gives me the same error, as well. Could you help me? Thanks
Ionice on cp - why I need set dir
linux;nice;ionice
If I understand you correctly, you are trying to change the ionice level for all subsequent calls to cp. If so, you are misunderstanding the way ionice works (and nice, for that matter).The ionice command refers to a process, not to a binary. You can use it either to change the ionice level of a currently running process, by giving it the PID as an argument, or you can use it when you start a process.So, either you keep watch on the machine and manually set a new ionice level for the problematic processes, like this: ionice -c2 -n0 -p 12345 # replace 12345 with the PID you want to act niceror you change the scripts you're working with so that they use ionice -c2 -n0 cp from to instead of just cp from to.There's still no guarantee that things will get better. IO is more complicated than you might think, and especially so if you're working with virtual machines.