Storage & Data¶
GPU workloads are data-heavy. This page explains where data lives on a DC Suite cluster, how long it survives, and how to get results out before you tear a cluster down.
Storage tiers¶
A cluster typically presents three tiers, each with different speed and durability characteristics:
| Tier | Backed by | Scope | Survives cluster delete? | Use for |
|---|---|---|---|---|
| Node-local scratch | The node's own NVMe/SSD | One node | ❌ No | Hot working set for a single node, checkpoints in flight |
| Shared cluster storage | A cluster-wide shared filesystem | All nodes in the cluster | ❌ No | Datasets and outputs shared across nodes/jobs |
| External / durable storage | Object store or NFS you mount | Outside the cluster | ✅ Yes | Source datasets, final artifacts, anything you must keep |
Cluster-scoped storage is ephemeral
Both node-local scratch and shared cluster storage are destroyed when the cluster is deleted. Treat them as scratch. Anything you need to keep must land in external/durable storage before delete.
Shared cluster storage¶
When you create a cluster you set a shared storage quota (GiB). That capacity is presented as a shared filesystem mounted on every node, so a multi-node job can read inputs and write outputs to one place.
- Sizing: set it to your dataset size plus headroom for outputs and checkpoints.
- Path: the mount point is shown on the cluster's detail page.
- Performance: shared storage is convenient but slower than node-local NVMe; for the hottest data, stage onto node-local scratch at job start.
A durable-data workflow¶
flowchart LR
EXT[(External durable store)] -->|stage in| SH[Shared cluster storage]
SH -->|per-job hot copy| LOC[Node-local scratch]
LOC -->|checkpoints| SH
SH -->|results out| EXT
- Stage in your dataset from durable storage to shared cluster storage once, at the start.
- For throughput-bound jobs, copy the hot subset to node-local NVMe.
- Write checkpoints to shared storage so a single node failure doesn't lose progress.
- Copy results out to durable storage before deleting the cluster.
Getting data in and out¶
- Small files:
scp/rsyncover SSH to the login node. - Large datasets: pull directly from your object store on the cluster (e.g. with the provider's CLI) into shared storage — much faster than pushing from a laptop.
- Results: push finished artifacts back to durable storage from a job's final step, so nothing depends on you remembering to copy before delete.
Checklist before deleting a cluster¶
- [ ] Final artifacts copied to durable storage
- [ ] Latest checkpoint safe outside the cluster
- [ ] Nothing important left only on node-local scratch
Next: Security & Isolation.