How to intermediate · 3 min read

Azure OpenAI reserved capacity explained

Quick answer
Azure OpenAI reserved capacity is a dedicated resource allocation model that guarantees enterprise customers fixed compute capacity for their LLM workloads, ensuring predictable performance and availability. It enables cost savings by committing to a fixed monthly usage and provides priority access to models like gpt-4o within the Azure environment.

PREREQUISITES

  • Azure subscription with Azure OpenAI service enabled
  • Azure CLI installed and configured
  • Python 3.8+
  • pip install azure-identity azure-ai-openai

Setup reserved capacity

To use Azure OpenAI reserved capacity, you must first enable the reserved capacity plan in your Azure subscription. This involves purchasing a reserved capacity SKU through the Azure portal or via Azure CLI, which allocates dedicated compute resources for your OpenAI workloads.

Reserved capacity provides a fixed monthly quota of compute units that you can consume with priority access to models, reducing latency and avoiding throttling during peak demand.

bash
az login
az account set --subscription "<your-subscription-id>"
az openai reservation create --name myReservedCapacity --sku "Standard_Dedicated" --capacity 1
output
Reservation 'myReservedCapacity' created with SKU 'Standard_Dedicated' and capacity 1.

Step by step usage

After purchasing reserved capacity, configure your Azure OpenAI client to use the reserved capacity endpoint. This ensures your requests consume the reserved quota and benefit from guaranteed capacity.

Below is a Python example using the azure-ai-openai SDK to call the gpt-4o model with reserved capacity:

python
import os
from azure.identity import DefaultAzureCredential
from azure.ai.openai import OpenAIClient

endpoint = os.environ["AZURE_OPENAI_ENDPOINT"]
credential = DefaultAzureCredential()
client = OpenAIClient(endpoint, credential)

response = client.get_chat_completions(
    deployment_id=os.environ["AZURE_OPENAI_DEPLOYMENT"],
    messages=[{"role": "user", "content": "Explain reserved capacity in Azure OpenAI."}]
)
print(response.choices[0].message.content)
output
Reserved capacity in Azure OpenAI guarantees dedicated compute resources for your workloads, ensuring consistent performance and priority access to models like gpt-4o.

Common variations

  • Use Azure CLI to manage reserved capacity quotas and monitor usage.
  • Switch between reserved capacity and pay-as-you-go by changing deployment endpoints.
  • Use asynchronous calls with azure-ai-openai for high throughput applications.
python
import asyncio
from azure.ai.openai.aio import OpenAIClient
from azure.identity.aio import DefaultAzureCredential

async def main():
    endpoint = os.environ["AZURE_OPENAI_ENDPOINT"]
    credential = DefaultAzureCredential()
    client = OpenAIClient(endpoint, credential)

    response = await client.get_chat_completions(
        deployment_id=os.environ["AZURE_OPENAI_DEPLOYMENT"],
        messages=[{"role": "user", "content": "What is reserved capacity?"}]
    )
    print(response.choices[0].message.content)

asyncio.run(main())
output
Reserved capacity ensures dedicated compute resources in Azure OpenAI, providing predictable performance and cost benefits.

Troubleshooting tips

  • If you receive quota exceeded errors, verify your reserved capacity allocation and usage in the Azure portal.
  • Ensure your deployment ID matches the reserved capacity deployment endpoint.
  • Use Azure CLI commands to check reservation status and renew or scale capacity as needed.

Key Takeaways

  • Azure OpenAI reserved capacity guarantees dedicated compute resources for enterprise workloads.
  • It provides cost savings and priority access to models like gpt-4o within Azure.
  • Setup requires purchasing reserved capacity via Azure portal or CLI and configuring your client accordingly.
  • Use Azure SDKs with the reserved capacity deployment endpoint to consume allocated quota.
  • Monitor and manage reserved capacity usage through Azure CLI and portal to avoid quota issues.
Verified 2026-04 · gpt-4o
Verify ↗