---
title: Cluster Overview Tab
sidebar_label: Cluster Overview
---
import { Grid, Cpu, Heart, Layers, AlertTriangle } from 'react-feather';
# Cluster Overview Tab
One screen answering "is the cluster healthy, and is it busy?" — summary cards, per-node health, and
the Slurm partition table.
},
{ href: '#node-health', label: 'Node health', icon: },
{ href: '#slurm-partition-info', label: 'Partition table', icon: },
{ href: '#the-gpu-health-banner', label: 'GPU health banner', icon: },
{ href: '#reading-the-tab-quickly', label: 'Reading it quickly', icon: },
]} />
The tab requires a **Running** cluster. Otherwise it reads *"Cluster overview is available when the
cluster is running."*
---
## Summary Cards
| Card | What it shows | Subtitle |
|------|---------------|----------|
| **TOTAL GPUS** | Every GPU across the cluster | ` nodes × ` |
| **ALLOCATED GPUS** | How much of the cluster is in use | ` nodes active` |
| **GPU UTIL** | Average GPU utilisation | `avg across active nodes` |
| **GPU MEMORY** | Average GPU memory in use | `avg used / GB` — the per-GPU capacity |
| **RUNNING JOBS** | Jobs executing now | ` pending in queue` |
| **IDLE NODES** | Nodes with nothing allocated | `available for workloads` |
:::note "Allocated GPUs" counts busy nodes
Despite the label, this card counts **nodes** that are allocated or partly allocated, not individual
GPUs. Compare it against **TOTAL GPUS**' node count rather than its GPU count. For exact per-GPU
allocation, use `scontrol show node` or the [Nodes tab](/docs/tir/SlurmCluster/manage/nodes).
:::
:::tip The two numbers that matter most
**IDLE NODES** and **GPU UTIL** together tell you whether the cluster is under-used. Idle nodes with
jobs pending means a scheduling constraint — the queue wants something the free nodes cannot give.
Zero idle nodes with low GPU utilisation means jobs are holding GPUs without using them, which is
usually a dataloader bottleneck.
:::
---
## Node Health
One card per node, with a coloured dot for its Slurm state. At most four are shown; a
**Show More (N more nodes)** link jumps to the [Nodes tab](/docs/tir/SlurmCluster/manage/nodes).
### States
| State | Dot | Meaning |
|-------|-----|---------|
| **IDLE** | Green | Up, nothing allocated. Ready for work |
| **ALLOCATED** | Blue | Every allocatable resource is allocated to jobs |
| **MIXED** | Yellow | Partly allocated — some resources free |
| **DOWN** | Red | Slurm has marked the node unavailable |
| **UNKNOWN** | Grey | Slurm is not reporting this node — usually the worker has not registered yet, or the controller cannot reach it |
The legend above the cards lists IDLE, ALLOCATED, MIXED and UNKNOWN. A **DOWN** node shows a red dot
even though the legend does not include it, and other Slurm states (`DRAIN`, `MAINT`, `RESERVED`,
`REBOOT_REQUESTED`, …) render grey.
:::warning UNKNOWN right after a change is normal; UNKNOWN that persists is not
A worker shows **UNKNOWN** for a short while after a restart, a scale-up or an image update while it
registers with the controller. If it is still UNKNOWN after a few minutes, that node is not joining —
check the [Logs tab](/docs/tir/SlurmCluster/manage/logs) for that worker, and consider
[Restart All Workers](/docs/tir/SlurmCluster/manage/actions#restart-actions).
:::
### Card contents
| Row | Shows |
|-----|-------|
| Title | The node, as `e2e_node_ (slinky-N)` — the physical machine and the Slurm node name |
| **GPU Util** | Average across the node's GPUs, with a bar |
| **VRAM** | Average per-GPU memory used, over per-GPU capacity |
| **Temp / Power** | Average temperature and power draw per GPU, colour-coded |
Temperature turns orange at 75 °C and red at 85 °C. Power turns orange at 300 W and red at 400 W.
:::tip Temperature colour is a real signal
Sustained red on one node while its neighbours are green usually means a cooling or seating problem,
not a workload difference. Note the node name and check the
[Nodes tab](/docs/tir/SlurmCluster/manage/nodes) for XID errors before opening a support case.
:::
---
## Slurm Partition Info
> Partitions you define are written to `slurm.conf`. The platform partition covering every node is
> managed for you.
| Column | Shows |
|--------|-------|
| **PARTITION** | Name. `*` marks the default. `not live` means it is in your configuration but the controller is not reporting it |
| **NODES** | Node count |
| **GPU TYPE** | Not currently populated — see the note below |
| **AVAIL / TOTAL** | Not currently populated — see the note below |
| **DEFAULT TIME** | Time limit applied when a job omits `--time` |
| **MAX TIME** | Longest a job may request. `∞` means `UNLIMITED` |
| **STATE** | `UP`, `DOWN`, `DRAIN`, `INACTIVE` — or `DISABLED` for one of yours that is switched off |
| **ACTIONS** | ⋮ with **Edit** and **Delete** for your partitions. Platform partitions read `Managed` |
An **Add Partition** button sits at the top right. Full documentation:
[Manage partitions](/docs/tir/SlurmCluster/slurm-configuration/partitions).
The footer records the source — `Sourced from slurmrestd · GET /slurm//partitions` — so the
table reflects the live controller.
:::warning GPU TYPE and AVAIL / TOTAL are not populated
These two columns are not fed by the partition data the console receives: **GPU TYPE** renders blank
and **AVAIL / TOTAL** shows a placeholder rather than real availability. Do not rely on them.
For authoritative per-partition availability, use the login node:
```bash
sinfo -o "%20P %5a %10l %6D %6t %N"
```
The [Nodes tab](/docs/tir/SlurmCluster/manage/nodes) shows real per-node GPU models and health.
:::
---
## The GPU Health Banner
A red banner appears at the top when any GPU reports an **XID error** — an NVIDIA hardware or driver
fault:
> **GPU / Node Health Issues Detected**
> ` node(s) DOWN · node(s) with XID errors · total GPU fault events`
Below it, one row per fault with the XID code, the node, the GPU index, and the error text.
:::warning The banner only appears for XID errors
A cluster with DOWN or UNKNOWN nodes and no XID errors shows **no banner**. Node state is on the
node cards above, not here — do not treat a missing banner as "all nodes healthy".
:::
XID errors mean the GPU or its driver hit a fault. Some are transient; some indicate failing
hardware. Investigate on the [Nodes tab](/docs/tir/SlurmCluster/manage/nodes#xid-errors), where a
single affected node can be rebooted.
---
## Reading the Tab Quickly
A 20-second health check before submitting a large job:
1. **Red banner?** → XID errors. Go to the Nodes tab before you submit anything expensive.
2. **Node cards** → any grey (UNKNOWN) or red (DOWN) dots? Those nodes are not usable.
3. **IDLE NODES** → is there room for what you are about to submit?
4. **Partition table** → is the partition you target `UP`, and does its **MAX TIME** allow your
`--time`?
5. **GPU UTIL** → if it is high, expect to queue.
:::tip This tab is a snapshot, not a stream
Nothing on it auto-refreshes. Use the refresh icon in the header, and for trends over time use the
[Monitoring tab](/docs/tir/SlurmCluster/manage/monitoring), which has selectable time ranges.
:::
---
## Related Resources
- [Nodes and GPU health](/docs/tir/SlurmCluster/manage/nodes)
- [Jobs tab](/docs/tir/SlurmCluster/manage/jobs)
- [Monitoring](/docs/tir/SlurmCluster/manage/monitoring)
- [Manage partitions](/docs/tir/SlurmCluster/slurm-configuration/partitions)