App and Docker Services expose a Scaling tab

It covers process replicas (concurrency) and default resource settings derived from your Procfile, Dockerfile, or platform defaults.

Database Services do not use this tab.

Prerequisites

• The Service has completed at least one deployment so process types are known.
• A Procfile or container entrypoint defines process types (for example web and worker). If none are detected, the UI may show No Process Types Found or guide you to the Defaults subtab.

Change replica counts

1. Open the Service → Scaling tab. The heading is Scaling, with the description: resource limits and process scaling.
2. Stay on Processes (first subtab) to adjust per-process Replica Count.
3. Use the form controls (stepper or input) within the limits shown for your Worker Node capacity.
4. Apply changes using the in-product Save / submit control for scaling.

Expected outcome: The UI shows the updated replica badge (for example 2 replicas). Work is applied through the platform queue; errors appear in toasts and Logs if the node cannot satisfy the request.

Defaults subtab

Open Defaults when the product reports No specific processes found or when you need baseline limits before named processes appear. Configure defaults, then return to Processes after the next successful deployment if new process types are detected.

Capacity limits

Maximum replicas and memory are bounded by Worker Node capacity. If you hit limits, add or resize compute (see Attach compute to an environment under Environments in the sidebar).

Screenshots

Recommended captures:

• Scaling tab with Processes and Defaults subtabs visible.
• One Replica Count card with the badge showing 1 replica or multiple replicas.

Related

• Redeploy and rollback
• Health checks and runtime behavior
• Compute and worker node issues