Mike Coleman wrote:
Here's a bash feature I'd love to see, but don't have time to implement myself: a "--free-slot" flag to 'wait' that will wait until there is at least one free "slot" available, where a slot is basically a CPU core.Example usage: $ for ((n=0; n<100; n++)); do my_experiment $n > $n.out & wait --free-slot 4 done which I would run on a quad-CPU host. The meaning of the wait is: if I already have four background invocations of "my_experiment" running, wait until one finishes, then proceed. (If there are fewer than four running, proceed immediately.) This provides a nice sloppy way of letting me parallelize in a script without having to complicate things. "make -j" and "xargs -P" provide some of this capability, but are a lot more work to set up--I'd really like to have this at my fingertips for interactive stuff.
I did something like that as a script, using an array of PIDs and a big loop and so on. I don't think it needs to be part of internal Bash features, it wasn't that much work.
J.
