Runs a pool of processs of a certain size each running the same command. When a process exits another process is started to maintain the pool size. The size of the pool is controlled via the keyboard.

gem install ppool

Usage: ppool [options] COMMAND ARGS...
    -s, --size SIZE                  Initial pool size
    -d, --delay MSECS                The delay between checking the state of the process pool (default 100ms)
    -t, --time TIME                  Time limit
    -b, --basic                      Basic (non curses) verion
    -r, --rmlogs                     Remove logs for processes that exited successfully
    -a, --average NUM                Number of processes used to calculate average elapsed time
    -l, --logdir DIR                 Log directory
    -h, --help                       Show this message

• -s, --size SIZE: Sets the initial size of the process pool to be SIZE (default 1).
• -d, --delay MSECS: The delay in milliseconds between checking the state of the pool (default 100ms). Lower values make the pool more responsive at the cost of higher CPU usage.
• -t, --time: Sets a time period after which the process pool is emptied. Time can be specified in the following formats SS, MM:SS, HH:MM:SS.
• -b, --basic: Use a basic version rather than curses based version.
• -l, --logdir DIR: Stores logfiles in the DIR directory (default './ppool-logs').
• -r, --rmlogs: Removes logs for processes that exited successfully leaving logs for processes that exited with a status > 0.
• -a, --average NUM: Uses the last NUM processes when calculating the average elapsed time. The default value is 0 which means the elapsed time for all processes are used.
• -h, --help: Display usage help message.

• '↑' or '+': Increase the pool size by 1. ↑ does not work in basic mode.
• '↓' or '-': Decrease the pool size by 1. ↓ does not work in basic mode.
• '0'..'9': Set the pool size to a value between 0 and 9.
• 'q': - Quit gracefully. This sets the pool size to 0 and waits for all running processes to finish before exiting.
• 'x': - Exits immediately.

Start a process pool of size 10 running the command './bin/test-cmd foo bar'

ppool --size 10 ./bin/test-cmd foo bar

Start a process pool of size 3 using the non-curses mode running the command './bin/test-cmd -n 2 -f bar'

ppool --basic --size 3 -- ./bin/test-cmd -n 2 -f bar

Start a process pool of size 10 running the command 'sleep 3' which exits after 5 minutes

ppool --size 10 --time 05:00 sleep 3

Start a process pool of size 5 showing the average elapsed time of the last 20 processes:

ppool --size 5 --average 20 ./bin/test-cmd