Today we are pleased to announce the public preview of Autoscale for Azure Event Grid namespaces. With this capability, an Event Grid namespace in the Standard tier automatically adjusts its throughput unit (TU) allocation in response to real-time workload utilization. This removes the need to manually provision capacity ahead of traffic changes or react to throttling after the fact.
How Autoscale fits with existing capacity management
Event Grid namespaces already provide control over capacity through throughput units. Each Throughput Unit defines a fixed rate of event ingress, event egress, MQTT publish, and MQTT client connections. Until now, customers set the Throughput Unit count at namespace creation and adjusted it manually when traffic patterns changed.
Autoscale builds on this model. It automates the adjustment of Throughput Unit count based on observed utilization. Customers still control the boundaries: a minimum Throughput Unit floor that guarantees baseline capacity, and a maximum Throughput Unit ceiling that caps cost. Event Grid handles all scaling decisions within those bounds. No manual intervention is required.
Why this matters
Event-driven and IoT workloads are rarely steady-state. MQTT device fleets connect in waves as regions come online. Event broker ingress spikes during batch processing windows or in response to external triggers. Multi-tenant platforms see delivery volumes shift across tenants throughout the day.
Fixed-capacity provisioning forces a trade-off: provision for peak and pay for idle capacity, or provision for average and accept throttling during spikes. Autoscale addresses both sides by adding capacity when utilization is high and releasing it when utilization drops.
Scenarios where Autoscale helps
IoT and MQTT workloads
Device fleets connect and disconnect on their own schedule. Message fan-out and subscription counts shift rapidly as devices move between online and offline states. With Autoscale, the namespace adds capacity as connection counts grow and releases it as devices go idle, keeping the MQTT broker responsive without manual resizing.
Example
A logistics company operates a fleet of 50,000 delivery vehicles. Each vehicle publishes GPS location and engine telemetry via MQTT every 10 seconds. During the morning dispatch window (6–8 AM), all vehicles come online simultaneously, generating a connection surge that is 5× the steady-state rate. Previously, the operations team had to pre-scale the namespace each morning and scale it back at night. With Autoscale, the namespace detects the connection ramp-up within seconds, provisions additional TUs to absorb the spike, and scales back down overnight when most vehicles are parked and idle—without any manual intervention.
Bursty event broker workloads
Periodic batch uploads, demand-driven spikes, or seasonal traffic patterns create short-lived peaks that are difficult to plan for. Autoscale provisions additional capacity during the burst and releases it once traffic returns to baseline, keeping costs aligned with actual usage rather than worst-case projections.
Example
An e-commerce platform processes order events through Event Grid. On regular days, ingress sits at approximately 2,000 events per second. During flash sales, ingress spikes to 40,000 events per second for 15-20 minutes before returning to normal. Before Autoscale, the team provisioned for peak capacity around the clock, paying for 20x the baseline even when traffic was low. With Autoscale, the namespace scales from 2 Throughput Units to the required capacity within seconds of detecting the spike, handles the burst without throttling, and releases the extra Throughput Units once the sale ends - aligning cost directly with the duration and intensity of each event.
How it works
Autoscale is a namespace-level configuration. Customers enable it and set a minimum and maximum TU count. Event Grid continuously evaluates utilization across all scaling categories. When utilization crosses internal thresholds, Event Grid adjusts the Throughput Unit allocation up or down within the customer-defined bounds.
Full details on scaling behavior are available in the Autoscale in Azure Event Grid namespaces (preview) - Azure Event Grid | Microsoft Learn.
What customers control
The configuration is intentionally simple:
Select Autoscale on the Scale tab to turn the capability on.
Minimum throughput units: The namespace will not scale below this value. Set this to cover baseline traffic so the workload is never throttled while the system detects a change.
Maximum throughput units: The namespace will not scale above this value. This caps cost exposure during peak traffic.
Everything else is managed by Event Grid internally. There are no scaling rules to configure or maintain.
Availability
Autoscale is available in public preview for Event Grid namespaces in the Standard tier. It can be enabled through the Azure portal, ARM templates or REST API. For detailed steps, refer to the how-to guide on Microsoft Learn.
What's next
This is a public preview release. We are actively evolving the experience and welcome your feedback. Feedback can be shared by contacting our support team directly.
Microsoft