myprog: don't hide program stdout/stderr. If your program finishes, the loop stops and we exit topp.Īlternatively, if you git Ctrl + C, the program also stops due to the trap: How do I kill background processes / jobs when my shell script exits? Where vsz is the total memory usage in KiB, e.g. In that case, the load behavior is implementation dependent (each thread might be reported as 100% busy or not).This form is useful if you want to benchmark an executable easily: topp() (

Trap 'for p in $pids do kill $p done' 0įor ((i=0 idash or older ksh), you can use this non portable syntax: for i in do. If you use bash, ksh93 and other shells supporting ranges, (i.e.

Each loop is able to load a CPU core at 100%. Each of them is repeating the null instruction ( :). How it works is quite simple, it starts four endless loops. This one-liner will load your four cores 1 at 100%: for i in 1 2 3 4 do while : do : done & done No need to install any extra package, your good old shell is able to do it alone.

Linux command line cpu usage