Set niceness to piped command

Question

I need to execute a set of "piped" commands with altered niceness level. Example:

nice -n 15 command1 | command2 | command3

In this case niceness is altered to "15" only for command1. How to change it for the whole set of commands (command1, command2 and command3)?

score 19 · Answer 1 · edited Jan 11 '18 at 06:30

19

 nice -n 15 sh -c "command1 | command2 | command3"

This sets niceness of a subshell, and the commands 1..3 inherit it.

edited Jan 11 '18 at 06:30

Kusalananda

answered Oct 06 '11 at 11:41

rozcietrzewiacz

score 13 · Answer 2 · edited Oct 06 '11 at 13:53

13

nice -n 15 command1 | nice -n <num> command2 | nice -n <num> command3

nice isn't used differently from any other command.

edited Oct 06 '11 at 13:53

Michael Mrozek

answered Oct 06 '11 at 11:40

nils

score 0 · Answer 3 · answered Nov 19 '18 at 09:26

0

exec command{1..26} runs all commands numbered 'command1' all the way to 'command26'

nice -n 15 $(pgrep command) renices any running process with 'command' in it

answered Nov 19 '18 at 09:26

jjisnow

1

`command` is very likely just a place holder. – ploth Nov 19 '18 at 10:30
I think there is a "race" condition here in that if any of the commands forks or starts another process, that one won't get picked up when changing the niceness. The other two answers set niceness at start so new processes will inherit that value – nijave Apr 10 '21 at 21:27

3 Answers3