llms.txt

# Deterministic Density

> A practitioner's editorial on deterministic virtualization, cgroup tiering,
> Effective Constrained Clock, and symmetric CPU capacity planning.

Deterministic Density is a documentation-first repository that publishes an
essay about CPU oversubscription, scheduler behavior, and why symmetric
Gold/Silver/Bronze cgroup tiering changes the economics of virtualization
density.

The essay compares AMD EPYC 9655 and EPYC 9575F as representative 2026-era
examples of dense, high-clock-frequency server silicon. It is not vendor
marketing or product affiliation material. The point is to examine how modern
high-density CPUs behave when the host is designed around deterministic tiered
capacity instead of flat-pool oversubscription.

## What it covers

- Traditional flat-pool oversubscription versus symmetric cgroup tiering
- Strict host isolation and guest-pool partitioning
- Effective Constrained Clock (ECC) as a contention-floor model
- Latency-tolerance workload mapping for Gold, Silver, and Bronze tiers
- Idle borrowing behavior under Linux CFS
- Capacity comparisons for mixed 2/4/8-vCPU VM estates
- OpenShift tenancy and cluster-estate sizing under 1:1, 1.5:1, and 3:1 tiered models

## Primary references

- OpenStack cgroup-tiering thesis: https://github.com/gprocunier/openstack-cgroup-tiering
- Calabi host resource management: https://gprocunier.github.io/calabi/host-resource-management.html
- Published essay: https://gprocunier.github.io/deterministic-density/

## Repository contents

- `README.md`: repository entry point and full essay text
- `index.html`: GitHub Pages entry point
- `assets/site.css`: shared site styling
- `scripts/build_site.py`: regenerates the README and Pages output from the source essay

## Source

- Repository: https://github.com/gprocunier/deterministic-density
- License: GPL-3.0
- Author: Greg Procunier