Provisioned throughput refers to the capacity for read and write operations on a database. Microsoft Azure Cosmos DB allows setting provisioned throughput at both container level and database level. For DP-420 exam aspirants, understanding when to use each level is vital.
When setting provisioned throughput at the database level, the set capacity is shared by all the containers within the database, thereby eliminating the need to set the throughput for individual containers.
When to Use Database-Level Provisioned Throughput
The choice of throughput level depends heavily on the application needs and the nature of the operations performed on the database. The following scenarios outline when database-level provisioned throughput can be beneficial:
- Small Applications: For applications with workload spread across multiple containers, the database-level provisioned throughput can be beneficial if individual containers require minimal provisioned throughput.
- Cost-Effectiveness: It is cost-effective for applications with numerous containers with moderate traffic as it removes the need to provision minimum RU/s for each container.
- Scalability: If you anticipate your application to scale up, adopting a database-level provisioned throughput allows for increased efficiency and reduced management overhead.
- Simplicity: If you want to simplify capacity management, database-level provisioned throughput can be beneficial as you need to manage provisioned throughput only at the database level instead of each container.
Let’s review an example of setting database-level provisioned throughput with the Azure Cosmos DB SDK for .NET:
CosmosClient client = new CosmosClient("connection-string");
Database database = await client.CreateDatabaseIfNotExistsAsync("myDatabase", throughput: 400);
In this snippet, a new Cosmos client is created and a database with a throughput of 400 request units per second (RU/s) is created if it doesn’t already exist. All the containers in this database will share the provisioned throughput.
Comparing Database-level and Container-level Provisioned Throughput
Database-Level Throughput | Container-Level Throughput | |
---|---|---|
Cost | Economical for small, multi-container workloads | Suitable for heavy, single-container workloads |
Scalability | Simplifies scalability | Requires managing each container separately |
Usage | Spread across all containers in the database | Isolated to a single container |
Control | Less granular control | Fine grained control |
In conclusion, the choice between database-level and container-level provisioned throughput won’t be the same for all scenarios but understanding the difference and appropriateness of each is a critical competency for any developer planning to take the DP-420 exam. This exam tests the ability to design and implement native applications using Microsoft Azure Cosmos DB, including database management techniques such as provisioned throughput.
Practice Test
True or False: The Azure Cosmos DB allows you to set provisioned throughput at the database level?
- True
- False
Answer: True
Explanation: Within the Azure Cosmos DB, you have the ability to set provisioned throughput at both the container and database levels.
What is the primary benefit of using database-level provisioned throughput in Azure Cosmos DB?
- A. Increased storage space
- B. Reduction in cost
- C. Enhanced security features
- D. Superior data processing capability
Answer: B. Reduction in cost
Explanation: Opting for database-level provisioned throughput allows you to share the throughput across all the containers in that database, which can help you reduce costs.
True or False: Provisioning throughput at the database level in Azure Cosmos DB helps to optimize data consistency.
- True
- False
Answer: False
Explanation: Optimizing data consistency isn’t directly related to database-level provisioned throughput. Provisioning throughput at this level is more about managing costs and performance, not data consistency.
Which of the following scenarios is best suited for database level provisioned throughput?
- A. When you have a large number of collections with low traffic
- B. When you have a small number of containers with high traffic
- C. When you need to perform complex queries
- D. When you have high data storage needs
Answer: A. When you have a large number of collections with low traffic
Explanation: Database-level provisioned throughput works best when there are many collections or containers with low, fluctuating traffic, as it distributes the throughput across all containers.
True or False: It is possible to switch from container-level to database-level provisioned throughput anytime.
- True
- False
Answer: True
Explanation: Azure Cosmos DB offers the flexibility to switch between provisioned throughput settings at any time based on your application’s requirements.
Which of the following Azure Cosmos DB APIs support database-level provisioned throughput?
- A. SQL API
- B. Cassandra API
- C. MongoDB API
- D. All of the above
Answer: D. All of the above
Explanation: Azure Cosmos DB’s SQL, Cassandra, MongoDB, and all other APIs support the establishment of database-level provisioned throughput.
True or False: You can lower the cost by using database-level provisioned throughput only if you have a large number of high traffic containers.
- True
- False
Answer: False
Explanation: Decreasing the cost by using database-level provisioned throughput is more beneficial when you have a large number of containers with low to medium traffic.
Which of the following isn’t influenced by the choice of database-level provisioned throughput in Azure Cosmos DB?
- A. Performance
- B. Cost
- C. Storage
- D. Scalability
Answer: C. Storage
Explanation: The choice of provisioned throughput (container or database level) doesn’t affect storage capacity, but it does influence the performance, cost, and scalability.
True or False: For a container in Azure Cosmos DB, the minimum database level provisioned throughput is 400 RU/s.
- True
- False
Answer: True
Explanation: Azure Cosmos DB sets 400 RU/s as the minimum provisioned throughput at both the container and database levels.
Which of the following is unnecessary to determine before choosing database-level provisioned throughput?
- A. Number of containers
- B. Traffic per container
- C. Total storage required
- D. None of the above
Answer: D. None of the above
Explanation: To choose the right throughput level, one should consider the number of containers, amount of traffic per container, and the total storage required. It helps in properly leveraging database-level provisioned throughput and managing costs effectively.
Interview Questions
What is database-level provisioned throughput in Microsoft Azure Cosmos DB?
Database-level provisioned throughput refers to the allocation of a set amount of capacity for a database that can be shared among its different containers. It is used to handle workloads in a cost-efficient way.
When would you choose to use database-level provisioned throughput in Cosmos DB?
You might choose to use database-level provisioned throughput when you have workloads with unpredictable traffic patterns, or when the database has many containers with minimal traffic, to optimally utilize the allocated capacity and reduce costs.
How does the use of database-level provisioned throughput enhance the scalability of Cosmos DB?
Database-level provisioned throughput enhances the scalability of Cosmos DB by allowing the capacity to be shared among multiple containers. This feature provides a more efficient and cost-effective solution for handling varying workloads.
What is the difference between database-level and container-level provisioned throughput?
The main difference lies in the allocation of capacity. Database-level provisioned throughput represents the shared capacity across multiple containers, while container-level provisioned throughput pertains to the designated capacity for an individual container.
How can database-level provisioned throughput contribute to cost efficiency in using Cosmos DB?
Database-level provisioned throughput can help reduce costs because you only pay for the total provisioned throughput, regardless of the number of containers. It becomes cost-effective, especially for databases with many containers that have minimal individual usage.
Is there any trade-off when using database-level provisioned throughput in Cosmos DB?
One trade-off could be possibly experiencing throttling on a busy container while another container is idle. As multiple containers share the throughput, a very busy container might consume most of the throughput and impact the performance of others.
Can you switch between database-level and container-level provisioned throughput as needed?
Yes, you can switch between database-level and container-level provisioned throughput. However, you should consider potential downtime during the switch and the costs involved due to throughput changes.
When should you not use database-level provisioned throughput in Cosmos DB?
You might not want to use database-level provisioned throughput if you have some heavily used containers that require dedicated capacity and could impact the performance of other containers in the database.
What role does the partition key play in database-level provisioned throughput in Cosmos DB?
The partition key plays a crucial role in efficiently distributing and scaling the allocated throughput across different logical partitions in Cosmos DB, ensuring optimal use of the database-level provisioned throughput.
How does Cosmos DB ensure fairness in the utilization of database-level provisioned throughput?
Cosmos DB ensures fairness by using an algorithm that equally distributes the provisioned throughput among all the logical partitions, depending on their usage and workload demand.
How is database-level provisioned throughput charged in Azure Cosmos DB?
For database-level provisioned throughput, you’re billed for the highest amount of throughput provisioned for any single hour during the billing period.
What are the implications of using database-level provisioned throughput for latencies and SLAs in Cosmos DB?
Under normal operations, using database-level provisioned throughput should not affect latencies and SLAs in Cosmos DB. However, under extreme conditions, you may observe increased latencies due to resources contention if one container consumes most of the throughput.
How do you monitor the usage of database-level provisioned throughput in Cosmos DB?
You can use Azure Monitor, built-in Azure Cosmos DB metrics, or the Azure portal to monitor and track the usage of database-level provisioned throughput.
How is database-level provisioned throughput configured in Cosmos DB?
Database-level provisioned throughput can be configured during the creation of the database or updated subsequently via the Azure portal, SDKs or CLI.
Can individual container maximum throughput exceed the database-level provisioned throughput in Cosmos DB?
No, an individual container’s throughput cannot exceed the total database-level provisioned throughput. It can, however, consume all of it, leaving no throughput for other containers.