Azure Cosmos DB each partition size limit

6
votes

In Azure Cosmos DB partinioned collection, does each partition has any size limit?

As per this old document, they have a size limit of 10 GB. Is that the same now also?

https://azure.microsoft.com/en-in/blog/10-things-to-know-about-documentdb-partitioned-collections/

Regards, Karthikeyan V.

2
azureazure-cosmosdb
The truly baffling thing is why there is an arbitrary limit at all. It seems like the 21st century version of the apocryphal "640K ought to be enough for anybody" gaffe... - McGuireV10

2 Answers

4
votes

A partitioned collection has individual 10GB partition spaces. For a given partition key, you cannot exceed 10GB of data. This has not changed.

You'll need to pick a partition key which distributes your data across many partitions, vs creating "hot" partitions which could fill up (where you'd then get an error when attempting to write content).

4
votes

There are two type of collection

  • Single Partition Collection (10GB and 10,000 RU/s)
  • Partitioned Collection (250 GB and 250,000 RU/s)- you can increase the limit as needed after contacting azure team.

For partitioned collection you mush have to specify a partition key based on your query filter for better read performance and if you will not mention it will be by default single partition collection.

Note: Collection is a logical space and it can span across multiple node(hence quorum) in background based on the RU and other param, in short it's a PAAS and the infra handling is automated behind the screen, you will not have much control over it.

More info here:

Partitioning and horizontal scaling in Azure Cosmos DB

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