Azure Cosmos DB
An Azure NoSQL database service for app development.
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Performance issue on CosmosDB for MongoDB
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Sanjay Mange
5
Reputation points
I am experiencing performance issue with CosmosDB for MongoDB (RU), when executing a query on a collection containing 300,000 documents. The query takes 43 seconds to execute on CosmosDB, whereas on my local MongoDB setup, it only takes 411 ms. Both env having the same data and same indexes + i have executed other queries also to evaluate and compare the performance and i am seeing significant performance difference. Additionally CosmosDB is on DEV environment so there is no traffic on the server.
What could be causing this significant performance difference ?
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ShaktiSingh-MSFT 14,281 Reputation points Microsoft Employee2024-07-04T09:22:10.0566667+00:00 Hi Sanjay Mange •,
Welcome to Microsoft Q&A forum.
As I understand, you want to know performance difference between MongoDB and Azure Cosmos Mongo DB(RU).
Performance depends on multiple factors:
1). Whether DB is Provisioned or Serverless.
2). Check RUs allocated.
Choose RU-based if
- You're building new cloud-native MongoDB apps or refactoring existing apps for cloud-native benefits.
- Your workload has more point reads (fetching a single item by its _id and shard key value) and few long-running queries and complex aggregation pipeline operations.
- You want limitless horizontal scalability, instantaneous scale up, and granular throughput control.
- You're running mission-critical applications requiring industry-leading 99.999% availability.
You'd like a multitenant service that instantly allocates resources to your workload, aligning with storage and throughput requirements.
Throughput is based on Request Units (RUs).
RU charges depend on the selected model: provisioned throughput (standard or autoscale) or serverless.
Could you please check configuration of your DB and share details.
Thanks.
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Sanjay Mange 5 Reputation points
2024-07-05T05:19:43.4466667+00:00 Hi @ShaktiSingh-MSFT We have set up the RU serverless, and from what I understand, this type of performance is extremely low in serverless.
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ShaktiSingh-MSFT 14,281 Reputation points Microsoft Employee
2024-07-08T04:03:30.3533333+00:00 Hi Sanjay Mange •,
Please try to increase throughput and if this does not help, we recommend you to raise support case so that dedicated engineer could look into your DB and provide solution.
Thanks.
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Sanjay Mange 5 Reputation points
2024-07-08T05:59:38.36+00:00 Hi @ShaktiSingh-MSFT , Is it possible to increase the throughput of a serverless RU configuration? To the best of my knowledge, a serverless RU setup will automatically adjust the RU based on traffic patterns. And since I can't seem to find it on the portal, if it is possible to increase the throughput, could you please tell me how to do that?
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