> ## Documentation Index
> Fetch the complete documentation index at: https://docs.tuneplane.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Capacity

> How busy the hardware is, and which hardware there is, on one page at /admin/capacity.

Two tabs at `/admin/capacity`, administrators only. They were always read together: one page says
how busy the hardware is and the other says which hardware there is.

| Tab | Path | Answers |
| - | - | - |
| **Utilization** | `/admin/capacity` | How busy has the cluster been |
| **Fleets** | `?tab=fleets` | Which machines exist, and what each Fleet is |

The old `/utilization` and `/fleets` links land here. `?tab=fleets/<fleet-id>` opens one Fleet's
machines, which fill the page on their own.

## The Utilization tab

| Region | What it shows |
| - | - |
| **Occupancy over time** | Cards held against cards available, per series |
| **Range** | The period the chart covers |
| **Idle and unschedulable** | Free cards, and cards the platform has excluded |

Unschedulable is not busy. A card lands there when health checks found pending ECC retirements or
uncorrected errors, or when a process outside the platform is holding it.

## The Fleets tab

A [Fleet](https://docs.tuneplane.ai/en/ops/fleets.md) is a registered, named set of machines that one backend manages, and it
is the thing a job or a deployment is placed onto.

| Column | What it is |
| - | - |
| **Kind** | `node`, `kubernetes` or `slurm`. It decides which executor runs the job |
| **Nodes** | Machines in it, with what each reported at registration |
| **Capability** | Whether it may be used for training, serving, or hosting environments |
| **Visibility** | Every project, or named ones only |
| **Inventory status** | `fresh`, `stale`, `unknown` or `partial` |

Those four inventory statuses are never rounded into each other. **An unknown reading proves
nothing**, so it refuses no job and admits none by fallback, and an unreported card count reads as
`null` rather than `0`. A backend that could not be reached is not a cluster with nothing in it.

Discovery says what exists. It never says what is free.

## What you can do

| Action | Effect |
| - | - |
| **New Fleet** | Register Nodes or connect a Kubernetes or Slurm cluster |
| Mint a Join Token | **`node` Fleets only.** See below |
| Drain a node | Withhold new work while existing work finishes |
| Change capability or visibility | What the Fleet may be used for, and by whom |

Only a `node` Fleet registers machines here. Kubernetes and Slurm manage their own nodes.
Join Tokens, node credentials and heartbeats apply only to `node` Fleets. Asking for one on a `kubernetes` Fleet
is refused rather than producing a record nothing can honour.

External inventory is read-only. The platform does not cordon a Kubernetes node or drain a Slurm
partition: a control plane that mutates somebody else's scheduler needs an argument this one has
not made.

## Next

[Fleets](https://docs.tuneplane.ai/en/ops/fleets.md) · [Hardware](https://docs.tuneplane.ai/en/ops/hardware.md) · [Settings](https://docs.tuneplane.ai/en/console/settings.md)


This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.