Determine Diego sizing

[ghost]

To ensure we can adequately service customers, as ops engineers we need to appropriately size our Diego deployment.

Acceptance Criteria

• [x] Establish manifest parameters with regards to size and number of Diego cells and other components
• [x] Determine and document thresholds where sizing should be adjusted

  Implementation Sketch

• Maybe look at how big our DEA footprint is?

[ghost]

Diego cells initially sized to match DEAs. Future sizing/scaling should take into account a number of factors, including current and anticipated workloads, risk tolerance and recovery performance characteristics in the event a cell or AZ goes offline where containers will come up on surviving cells. See scaling notes at https://docs.cloudfoundry.org/concepts/high-availability.html#processes

[ghost]

Note that garden-linux has a default of 250 max_containers, and it is not recommended to increase beyond that.

https://github.com/cloudfoundry/garden-linux-release/blob/develop/jobs/garden/spec#L63