system requirements to build pacific

Hi folks, I'm seeing some of our internal Red Hat builders going OOM and killing ceph builds. This is happening across architectures. Upstream our braggi builders have 48 vCPUs and 256GB of RAM. That's not small. What is the minimum memory and CPU requirement for building pacific? Internally, to use one ppc64le example, we're running with 14Gb RAM and 16 CPUs, and the RPM spec file chooses -j5, hitting OOM. We tuned mem_per_process from 2500 to 2700 a while back to alleviate this, but we're still hitting OOM consistently with the pacific branch now. - Ken