When switching from c4 to m4 instances of similar memory sizes (but with fewer CPUs), we're seeing similar task runtimes with the same level of parallelism in one-off patch builds.
We'd like to be able to change the resmoke job factor on a per-distro basis. For m4, we will set it to 1.618 instead of 1, which is the default now .
The job factor will apply to Enterprise RHEL 6.2 and Linux DEBUG and will be a change in evergreen.yml. The job factor will be changed in evergreen_resmoke_job_count.py