----- Original Message -----
From: "Hartwig Hauschild" <openstack@hauschild.it> To: openstack-discuss@lists.openstack.org Sent: Tuesday, April 30, 2019 9:30:22 AM Subject: properly sizing openstack controlplane infrastructure
The requirements we've got are basically "here's 50 compute-nodes, make sure whatever you're building scales upwards from there".
It depends what's your end goal. 100? 500? >1000 nodes? At some point things like Nova Cells will help (or become necessity).
The pike-stack has three servers as control-plane, each of them with 96G of RAM and they don't seem to have too much room left when coordinating 14 compute-nodes.
96 GB of RAM per controller is much more than enough for 14 compute nodes. There's room for improvement in configuration.
We're thinking about splitting the control-nodes into infrastructure (db/rabbit/memcache) and API.
What would I want to look for when sizing those control-nodes? I've not been able to find any references for this at all, just rather nebulous '8G RAM should do' which is around what our rabbit currently inhales.
You might want to check out Performance Docs: https://docs.openstack.org/developer/performance-docs/ For configuration tips, I'd suggest looking at what openstack-ansible or similar projects provide as "battle-tested" configuration. It's a good baseline reference before you tune yourself. -Daniel