We have a master job (using the Multijob plugin) which launches eight sub-jobs in our CI pipeline. We have installed the least load plugin to evenly distribute the load on our (currently two) Jenkins slaves. However, we often see that seven jobs are launched on one slave and only one on the other.

My guess is that since the jobs are launched at exactly the same time, the least load plugin doesn't have time to see the new jobs launched on the slaves when it gets requests to map the other jobs, thus placing them all on the same slave.

If there's no cleaner solution available, then I'd suggest that the plugin would remember the jobs it has mapped to a particular slave for a few seconds, and factor them into the load balancing decisions within that time frame.