OpenSearch Serverless OCU usage too high

Question

So, I have created an instance for production use - and all its doing right now, is to index data from clients just so we have a baseline, I haven't enabled or displayed the main search functionalities.

We understand that the indexing OCU is taking a beating since we have a lot of requests coming in - but what I don't undestand, and my main question is: why is the search OCU maxed out as well and running 24/7? When we aren't even doing any calls to the search api to begin with and all our operations are only for indexing

See screenshot below:

![Enter image description here](/media/postImages/original/IMIBOChNMQTCyW_0kiwaCPdw)

Didier_Durand · Answer

Hi,

this page details the algorithms to scale OCUs up & down. It also details how to limit them if you wish:https://docs.aws.amazon.com/opensearch-service/latest/developerguide/serverless-scaling.html

```
When you create your first collection, OpenSearch Serverless instantiates a total of four OCUs 
(two for indexing and two for search). These OCUs always exist, even when there's no indexing 
or search activity. All subsequent collections can share these OCUs (except for collections with 
unique AWS KMS keys, which instantiate their own set of four OCUs). If needed, OpenSearch 
Serverless automatically scales out and adds additional OCUs as your indexing and search 
usage grows. When traffic on your collection endpoint decreases, capacity scales back down 
to the minimum number of OCUs required for your data size. At most, it will scale down to 
2 OCUs for indexing and 2 OCUs for search.
```

So, you can't go below 2 + 2 OCUs. Those 4 OCUs will get charged to your account.

Best,

Didier

OpenSearch Serverless OCU usage too high

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