Limiting the amount of parallelism

[joelzimmer]

How does concurrently decide how many processes to spawn? We have CI machines that have a lot of cores, but only have a small number available to work on. Can we limit the number of processes that are active at a given time?

[gustavohenke]

Hello @joelzimmer,
Unfortunately there is no way to limit the parallelism. concurrently just spawns all of the passed commands at the same time.

However, I'm open to suggestions on how to tackle this, taking in consideration existing features such as restarting, killing other processes, etc.

[joelzimmer]

@gustavohenke This is no longer a problem for us anymore (we're using slightly different build tactics in an upgraded system), but I'd look at parallel-webpack for inspiration - it'd be nice to pass in a limit of how many processes run and then queue which processes run.

[callumlocke]

Another use case for this: temporarily setting the limit to 1 (i.e. to run all commands in series) while you're trying to debug something, to make it easier to read the stdout logs.

[gustavohenke]

Duplicate of #175

[gustavohenke]

Published v5.2.0 with a --max-processes flag 🚢