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Scaling And Storage

Moltern lets supported workloads change size from the UI. Some apps can also mount persistent filespace.

Application Sizing​

Supported web service applications can adjust:

  • Replicas.
  • CPU per replica.
  • RAM per replica.

The resize panel includes:

  • Current values.
  • Proposed values.
  • Monthly run estimate.
  • Plan impact.
  • Warnings or violations.
  • Apply button when the preview is allowed.

Service Sizing​

Supported services can adjust:

  • CPU.
  • RAM.
  • Storage when the service supports it.

Service storage growth may be one-way. If the UI warns that storage can grow but not shrink automatically, treat the change as permanent for planning purposes.

Resize Workflow​

  1. Open the workload detail page.
  2. Enter the proposed size.
  3. Click Preview.
  4. Read plan impact and warnings.
  5. Open Billing if the preview is blocked.
  6. Apply only after the preview is allowed.
  7. Watch status until the workload returns to running.

Replicas​

Replicas run multiple copies of a web service application.

Increase replicas when:

  • The app needs more concurrency.
  • You want better availability during normal traffic.
  • The app is stateless or safely handles multiple instances.

Do not increase replicas when:

  • The app writes to local files without shared storage.
  • The app assumes only one process is running.
  • The database or external dependency cannot handle extra traffic.

CPU And RAM​

Increase CPU or RAM when:

  • The app is slow under expected load.
  • The app is killed or crashes because it lacks memory.
  • A build or runtime process needs more capacity.

Prefer measured changes:

  1. Change one dimension at a time.
  2. Preview cost impact.
  3. Apply.
  4. Watch behavior.
  5. Keep a note of why the size changed.

Shared Filespace​

Shared filespace is available for web service applications.

Use it for:

  • User uploads.
  • Generated reports.
  • Runtime assets that must persist after redeploy.
  • Files consumed by the app from a mounted path.

Avoid it for:

  • Databases that should be deployed as database services.
  • Cache data that can be regenerated.
  • Secrets.
  • Large unplanned dumps.

Read-Only Filespace​

Use read-only mode when the app should consume mounted files but not modify them.

Use read/write mode when the app must create or update files.

Storage And Billing​

Storage can affect plan limits and usage. Before adding or growing storage:

  • Confirm the workload owner needs persistent files.
  • Check current storage usage in billing.
  • Review whether the storage can be reduced later.
  • Document cleanup expectations.

Cleanup Checklist​

  • Delete unused preview environments.
  • Delete abandoned services.
  • Remove old static releases only when rollback is no longer needed.
  • Review reclaimable storage in billing.
  • Right-size services after experiments.
  • Keep owner notes for stateful services.